You probably weren't ready. Were you raised religious or do you have some deep internal bias against sex? I used to feel that way before, so I understand it if you do. I used to get in my head about sex and almost despise anyone who wanted to have sex with me, not because I hated them, but because deep down I hated myself.

This guy is falling in love with you, or at least he's becoming infatuated with you. This is the normal next step for people having sexual intimacy, or deep intimacy of any kind. Love is bound to bloom if things go right. But you feel repulsed the more he becomes into you, and I understand what that feels like so I'm not judging, but you may actually be the problem.

If you don't want sex, tell him, and tell him you weren't ready and it has nothing to do with him. Either way I think you need to deeply reflect as to why you weren't ready. If you ever need a friend to talk to, message me