He probably wasn't even laughting on at you. What probably happened was that his friend was saying something as he was looking at you and laughed at what ever his friend said. I do that a lott becaus we when guys are walking they look aound at girls but are still talking to each other. Don't think anything off it he probably didn't even think you noticed.
It was just a friendly act or maybe he was talking to that person and that person said something that caused laughter to him and it just had happened that he was looking at you. You should just go on and chances are you are not going to talk to him and maybe if you do he won't even remember
Honestly, work on your self esteem. Then you won't care what total strangers think. Why even waste time analyzing something like this? You'll never know the answer, it's pointless. If you didn't know him I highly doubt it was personal and even if it was, who cares? YOU DIDN'T KNOW HIM. Obviously he was the one with the problem if that was the case so don't bother wasting another second on it and work on yourself and what's real.
Neither good or bad. I wouldn't look anything into it. Sounds like you have a boyfriend. Just let it alone. Why cuase a problem within your relationship if you don't need to? I think the guy was just being silly. Hugz.
I don't think that its something to even worry about. You are really dwelling over nothing. He probably didn't even realize that that happend. A lot of times that's the case (with guys) (in my personal experiences)