as salam alaikum
Allah is All-Forgiving and although we should always fear His punishment, we should also always hope in His mercy. If the servant has remorse for the sin he/she has committed and resolution not to commit it anymore, Allah accepts his/her repentance. The bad feeling for having committed a sinful act may be a sign of the presence of certain degree of faith in the heart, no matter what people may do or think is relation to it. What matter is Allah's consideration and "indeed Allah loves those who repent and those who purify themselves" (2:222). Never underestimate your sins, neither take them lightly, but focus on serving and obeying Allah as make-up for your past shortcomings, and inshallah you will be successful.
With prayers of your success.