The thought of having sex with my boyfriend makes me anxious

Before last night I have been totally fine with having sex with my bf, but last night we started to mess around and things were going fine, then all of a sudden I just felt repulsed by the idea of going through with it and having sex. I couldn’t even say I love you back to him (which is something I’ve been struggling with lately, and can’t admit to myself about very well). We stopped soon after because we were both kinda tired. After I just laid there feeling nauseous, and anxious, and just grossed out. Now I’m doubting that I want to be with my boyfriend and it’s scaring me because I don’t want to break up with him and I do want to be with him. I’m just so confused and upset and really need advice.

I feel I should also mention, in church that morning we were preached to about premarital sex and how “disgusting” it was, so it could have something to do with that??