Aio or should I stop talking to him

I’ve been talking to this guy for about a month now and I’m starting to wonder if I should just stop talking to him altogether.

At the start he was VERY consistent. We’d talk constantly, stay up until like 6am talking, he replied really fast, always seemed interested in talking to me etc. He told me early on he wasn’t looking for a relationship which was honestly okay with me.

We ended up sleeping together and he stayed at my house. Since then though, his energy has completely changed and I feel like I’m going insane trying to figure out if I’m overthinking it or not.

He still talks to me/snaps me every day, but it’s way slower now and only will have a conversation if it’s me who starts it . Like leaving me on delivered for hours, not really starting conversations as much, just generally more distant than before I did ask him about this on two separate occasions and one he was just in a bad mood all week due to having to travel every day for work another response was he wasn’t going to be talking to me all day if he’s with his friends (I completely agree with the second one btw). But then when we actually see each other in person he’s affectionate, cuddly, talks normally to me, etc, so I genuinely cannot read this situation at all.

One thing that also bothered me was we were out one night after he stayed over and I saw him kiss another girl in front of me. Later that night I still ended up back at his house and he basically said “we’re just friends” and that he doesn’t want a relationship.

I know technically he hasn’t done anything wrong because he was honest from the start, but I think the sudden change in effort after we slept together is what’s getting to me.

Am I being dramatic/overthinking this or does it sound like he lost interest after sleeping with me? And should I just stop talking to him before I get more attached?