Why do guys treat me so weird?

Whenever I meet guys (in random places) it’s always strange. One time I met this guy, I was extremely tired that day, so I was yawning a lot. And every time I yawned, he laughed-Was he making fun of me?
Another time -i kinda spent the day helping out at this place, so a bunch of people were stuck together (me included) – and a guy there came over to me when I was busying doing something and just tucked my hair behind my ear. It would have been cute if I knew him… honestly it was really weird.

A while ago I knew this guy and he was my friend-ish (I was never sure) like we would get along but we would also not get along…
I don’t really know..everything is strange in general.