I love having sex but why do I feel so guilty after doing it?

I love my boyfriend and he makes me feel good. Him and I dated for over a year, then broke up for about 4-5 months because our individual situations were bringing frustration in our relationship. We had regular sex during our relationship. We just started seeing each other again in the beginning of this month.

The sex is amazing but after we finish I just feel really guilty and just disgusting in general. Like in my head, I’m thinking like what if I’m giving in too much and what if I look weak by having sex too quickly. It’s almost like I feel like a whore or something. I have asked him if he thinks I’m easy or if he just wants to be FWB with me, and he says no, he wants to be in a relationship with me and nothing else. But why do I still feel like shit after doing intimate stuff with him?