(latin girl, so please forgive me if I have a mistake grammatically speaking)

I want to ask you something and pleas tell me your advice or your opinion if it is possible.

I am in a 3 years relationship and I am still a virgin for you to know.

but talking about the problem and actually my question, when I am with my boyfriend like making out but moving* (see below), I feel at the beginning so great; I feel a super cool something and that's how I know I'm getting really wet and that feeling is awesome but really really quick; even though, after that 10 seconds feeling, I start feeling like uncomfortable? I don't know if that's the word that could describe it. I feel like weird and I want to stop making the movements.

so, I want to ask you if someone has feel the same or if it's just me. also, comment below what do you think about what is that and how could I fix it.

*: that we are kissing and I am on top of him and we are like recreating the movement that someone should do while having sex; I don't know its name in english