Trip fizzled out on awkward note

I went to see two friends in london for the weekend. Today was the last day and we were at the casino. They were playing a tournament but I was too tired so I decided to have a walk around outside instead.

A while later I got a text from one of them saying he’s done but couldn’t find me and left home, it was nice to see me etc. I went back in to see if the other friend was there but couldn’t find him. I texted him something random last night and he didn’t reply so I didn’t want to double text and ask him what he’s up to. He’s a very friendly person but I always have a feeling I might be bothering him so I thought I’d wait for him to text me. That’s something he did the other day anyway.

Well he didn’t. I waited around there for ages in case he’s out and wants to do something but nothing. I’m feeling very awkward and gutted about it now, that he probably doesn’t care to hang out with me and didn’t even bother saying bye. With this much time passed it’d be worse to reach out now. Pretty upset especially since I quite liked to be better friends with him, and am not the most outgoing so I take socia rejection very personally. What should I do?

Edit: 21M