Yeah that tail wag looks annoyed to me. Looks like the cat is trying to remain calm and patient despite how he feels so he’s separating himself from everyone.

The only thing missing is the licking of the lips. I’ve noticed a few cats and dogs do that when they are uncomfortable and I feel like this cat may have done that too. It’s like a gulp and licking of the nose a few times, like 2-3 times. Could be breed dependent, though, but likely happened before this video was taken.

The move from laying on his belly to starting to lay on his side is a good sign he’s not too annoyed/angered and is calming down. Bellies are very vulnerable positions for both cats and dogs so for them to start to show it is a good sign they’re in a good mood/comfortable and not on edge. It’s a very slight change I see near the end of the video.

This could be because you followed him. He wanted space and he feels violated, for lack of a better term, because you’re following him when he wants to be alone.

I’d say just give him space and let him come back when he feels up to socializing again.