Doubt is a mental state in which the mind remains suspended between two or more contradictory propositions, unable to assent to any of them.
Yes, we can pray for them as far as we are not sure that they are disbelievers.
Doubt in the number of the units (Rak'ats) has different types, some of the doubts are irreparable and Salah is invalid if doubt remains like doubt during morning and Maghrib Prayers and doubts in the first two Rak'ats in any Prayer.
There are repairable doubts which are during any of the four units Prayers (Dhuhr, Asr and Isha) if it happens after completing the second Rak'ah.
Your doubt between third or forth Rak'ah is repairable. You should consider your Rak'ah as the forth and complete your Prayer then stand up for just one Rak'ah of Salatul Ehtiyat which is just reciting Sura Al-Hamd then Ruku' then two Sajda then Salam.
You wrote that you performed another unit. That made the number of units reach to five which is incorrect.
You should repeat that Prayer to be sure that you fulfilled a proper Prayer of four units only.
Repeated doubts in worship acts like Wudu, Ghusl, Namaz etc should ignored.
It is always good to seek forgiveness even if you are not sure about the sin. The Prophet (SAWA) used to repeat Istighfaar despite the fact the he was the greatest Infallible. Istighfaar by itself has lot of benefits in our life here and hereafter.
There isn't a fixed yes or no answer to this question - it depends on your circumstances and yourself.
Personally, I think it is extremely helpful for people going into the study of Islam to have another career or vocation. This keeps you from financial dependency or desperation and makes you more free to study what you like for however long you feel is beneficial. This is especially if you are female and financially responsible for yourself or others, since men have certain financial opportunities that women don't; for instance, most imams of mosques are men, and usually men have more opportunities for paid services such as tabligh and majalis.
Then, in the future, if the opportunity arises, you could shift to work in the area of Islamic studies, or full-time studies, if that is what seems right.
So, you could try to do both - that is, maintain a separate job or career path, and do Islamic studies part-time on the side. (If you are not already doing this, and if you have the time and energy for it, of course - it is a commitment.) This would also allow you to see if it is right for you; for instance, some people think they want to go to hawza or do full time Islamic studies, but then decide after a couple years that it's not the right thing for them, and then sometmes it is a lot of work to get back onto a different career track.
Of course, the drawback is that you will miss out on an immersive experience, such as living at a hawza, but it can be a good way to feel things out.
You could consider what career you might pursue after your studies - for instance, working at a mosque, chaplaincy, university teaching, madrasa teaching, writing/translation, counselling, tabligh, or something completely different - and how available work is in that area, and much you would expect to earn.
You could also consider your skill sets that you would use after your studies - for instance, whether you feel most comfortable with things like leadership, management, oratory, social work, academics, and so forth. Of course, sometimes we discover that through experience.
Conversely, you could also look at yourself as an engineer - is it something that suits you and feel like you would miss if you left it and see a future for yourself in, or is it something you don't think you would get much further with or feel blocked in.
If you are 100% committed to pursuing Islamic studies, don't worry about negativity from people around you; however, it is still good to pay attention to some of the practical considerations they might bring up.
Similarly, if you are 100% committed to pursuing Islamic studies, then I would say just trust in Allah and go forward with it. The above advice is for if you are not certain.
Sometimes, Allah makes the decision easy for us by forcing us one way or the other! However, in the meantime, of course, pray for guidance and talk to people around you.
Allah does sustains us, but the reality is that many people who work in this area suffer from financial frustrations, unless they have a secure and suitably paying position of some sort, or other resources (inheritance, investments, etc).
I will leave you with a short story. Back in my younger years, when I was attending university, I used to study computer science (which was very competitive to get into and we were considered the lucky ones who were on top of the world). I decided that I was going to pursue Islamic studies and begin that by changing my major to Near Eastern Studies (the closest thing to Islamic Studies).
So, I went to one of our professors, a well-known Muslim, and told him the good news. "I'm going to change to a Near Eastern Studies major," I said.
He looked at me and said just one word. "DON'T."
Anyway, I did it anyway, but I have come to understand why he said what he did.
Our worst enemy (Shaitan) tries to disturb us in different ways including creating doubts in our minds which can be blasphemous and very disturbing. Our feeling that these doubts are bad is a sign that we reject it and don't believe in it. We need to deal with any doubt with proper thinking to be very clear that these doubts are untrue. We also need to seek refuge in Allah from satanic whispering by repeating (A'OOTHO BILLAH MINASHSHAITAN ARRAJEEM أعوذ بالله من الشيطان الرجيم
Repeating LA ILAAHA ILLALLAH لا إله إلا الله is also very useful in driving away Shaitan from our mind.
Repeating reciting Sura Al-Tawheed is also very useful in this regard.
Generall, any form of Thikrullah ( remembering Allah) is useful for protection from satanic evil.
'You should not feel guilty because you did not believe in the Satanic doubts, but keep on seeking refuge in Allah and seeking His help and support.
Thank you for your question. It depends on the type of doubts in your mind. If you have inner certainty on these matters but at the same time have waswas that even shocks you at times, this kind of waswas needs to be ignored completely. It is like someone proviking you who will say anything just to get a reaction. You won't prove anything as that is not the goal and it definitely is not haram to ignore this kind of waswas as it is the cure for it.
But if those doubts are deep within your being and not just on the surface of your mind, you should look for answers from those who are able to answer them to your full satisfaction. At the same time, if these doubts are within you then it is important to seek help from the Divine to show you that which will satisfy your doubts. Allah will guide you as He has guided those before you.
May you always be successful
Doubts come from our worst enemy, Shaitan. Shaitan wants to disturb the believers and deceive us. Doubts should never harm the believer who thinks in a proper way. You write that some of the doubts are very nonsensical. This means that you know that it is nonsense. Such nonsensical doubts need no effort to refute as you know that it is nonsense. Any doubt which you think it disturbing you, needs to be refuted with evidence. You can ask authentic scholars or refer to authentic books or websites.
We in Shia Islam don't have any question with out proper answer, and no doubt is left with out logical reply.
Real Islam of the Prophet (SAWA) and Ahlul Bayt (AS) provides authentic answer to any question and full explanation to every doubt.
You should never feel disturbed from any question or any doubt, but face it frankly and seek the answer from authentic scholars.
You mentioned a question: How to know that the higher power is Allah?
Answer: Allah is Creator of every creature in the universe and the sophisticated system in the creation and creatures proves that The Creator is One. Had another Gid existed, he should have declared his existence to the creature. Imam Ali (As) said : Had your Lord had a partner, the claimed partner should have sent messengers to people. All the messengers from Allah are the most noble and most truthful persons and all of them brought the message of Tawheed as the biggest fact in the existence.
You also mentioned a question: How to know that Quran is really from Allah?
Answer: The miracles in Quran prove with no doubt that Quran can never be from human source. Quran challenged the enemies who claimed that it is not from Allah, to brig any book like Quran using the help of every human and Jinn ( Say: If all human beings and all the Jinn join all their efforts to bring like this Quran,they will never bring like it, even if all of them joined their efforts)(Sura 17, Verse 88). When they failed, Quran challenged them to bring ten chapters similar to Quranic chapters which are 114 chapters. (They claim that Quran was created by you, Say: Bring you ten created chapters like Quran and call who so ever you can to help you other than Allah if you are truthful) (Sura Hood, verse 13). When they failed to do that again, Quran challenged them to bring just one chapter like Quranic chapters (If you are doubt about what We revealed on Our servant, then bring one chapter like it and call all you supporters besides Allah if you are truthful.) They again failed. This itself is an evidence that Quran is above the abilities of humans and Jinns and it is from Allah.
Scientific miracles in Quran also prove that it is from Allah. You can search in the internet (scientific miracles in Quran).
These questions can be from Satan to disturb you but you should worry but get the answer from authentic scholars.
Ignorance can be unavoidable and can be avoidable. Unavoidable ignorance is of those who have to access to knowledge like those who live and die in far away forests or remote areas with out any access to learning or asking knowledgeable persons. Unavoidable ignorance is not entitled to punishment because it was imposed on the ignorant and he had no choice.
Avoidable ignorance is a result of laziness or not caring to gain knowledge. Such ignorance is not pardoned. The narration states that sinful person will told on the Day of Judgement : Why did you fail to do good? He replies: I did not know. He will told: Why did you fail to learn? Then he will be punished.
'This means that gaining compulsory knowledge is also compulsory and those who were able to gain it,byte they opt to ignore or don't care for gaining the compulsory knowledge are responsible about their ignorance, unlike those ignorant who had no access at all to knowledge.
Simply, everything is Taahir for you unless and until you know for sure that it is Najis. This is a rule in jurisprudence based on a narration of Ammar from Imam Jafar Al-Sadiq (AS) stating : Everything is ritually clean till you know that it is ritually unclean. (Wasaa'il al-Shia, V.2, Section 37 on Nijasah).
Your doubt in this matter does not make any difference. You are ritually clean because you are just doubting and not sure that your body became Najis.
We have covered the topic of waswasah and doubts in tahara a few times, and you are able to search in the Q&A on the topic of waswasah and taharah.
The simple rule of thumb is because you are doubting, you consider it all to be tahir. Nothing more.
Please watch this clip, which is a part of a lesson I gave on taharah and najasah. Hope it will be of benefit.
The discharge a woman experiences is tahir, even if it is due to lustful thoughts, as long as it was not an orgasm.
She does not need to do ghusl, or anything else.
And Allah knows best.