1. When you know that Allah does not allow any marriage between a Muslim female and a non Muslim man and you write that "you feel that you went against Allah", you must repent and seek forgiveness and come back to Allah and never insist on doing wrong.
2. If you can convince the man and explain to him how to become a Muslim, then you need to recite a marriage agreement (Nikah) between you and him after becoming a Muslim in his heart.
3. If he refuses to become a Muslim, then there is no way that you can remain with him.
4. You must save yourself and your future from sinful acts.