Moved on or covering up?

Not too long ago a boy asked me out but I didn’t like him. Then not to ling after he got a gf. Some ppl r saying he might of done it to cover up getting turned down and that he might still like me and is using his gf.

Or that he might of just been desperate to get a gf.

Only reason I’m not sure is cuz his friends still tease him about me whenever I’m around. And I’ll catch him lookin over at me and stuff. What do u guys think? Obviously I can’t be totally sure but if u had to guess?

(I kinda like him and regret it)