First drunk hookup advice

I’ve never hooked up with anyone else while I am drunk. But, last night a neighbor and I grabbed some drinks with other neighbors, one thing led to another, and I ended up at a his place and we had sex. We were both too buzzed for it to be that great, but it was fun. I stayed over at his place and we both woke up late and hungover, agreeing to just not mention it to anyone else. For some reason I feel guilty though. Is that normal? I’ll be seeing him again since we are in the same apartment complex, and he seems chill. So, why do I feel so ashamed?