Help me live

My bf and I have been together for 3 years, and have been having sex for about a year now. He was my second partner, I had sex once with an ex and it was literally a complete blur. But any who, that's not the point. The point is 99% of my sex life has been with my current boyfriend. Sex is good, but I mean I don't really have anything to compare it too.

Now my question is, how do I know if he enjoys sex? I sometimes feel like I'm too "loose", if that makes any sense, and I don't know if that's normal or I'm just overthinking it. It's not like I've been engaged in these activities for long which is why im concerned if there's maybe something wrong with me or? He's never said anything about it, but it's usually when we start I can feel the tightness and by the end it's just a really loose feeling. I can feel him in me and he's a pretty decent size, except I can't push that thought from my head. We are pretty active, and tend to see each other a few times a week and when we do well usually go 2-3 times. We just introduced oral sex, (bc of my lack of experience, I was hesitant to having oral sex, he was super patient and gave me my space until I decided to try it) and it's amazing! Our sex life has been pretty basic and it's mostly in part of me being scared, what can I try or do to step up our sex life a little more? For obvious reasons I want to please him as he constantly pleases me, but I have no idea how to or where to start??