What Now? Please Help a Girl Out!

GEM

So my boyfriend and I have been together for over a year and at last had sex both for the first time! It was AMAZING and I don’t regret it at all. We were safe and cautious, but also loving and passionate at the same time. We’ve done it again and are experimenting, but I think something is off. When we are done I joke around and flirt with him but he just seems annoyed and distant. I ask him whats wrong but he says nothing and then remains silent until I initiate conversation again. We’ve only done it twice and I’m not gonna lie y’all I get really horny (maybe even too much), but he used to love it. I need help y’all do I back off and stop with the sex or keep going and hope it just changes?