Nut on the F train

I was on the F train tonight and there was this guy is a really gay looking hat (though you could make a similar case for my hat) who just pushes me for no apparent reason (except perhaps to be standing closer to the door when it would open at Delancy street. So I gave the guy some dirty look and continued talking to a friend who was also getting off at Delancy. I was not getting off at that stop. So then the guy says "I can't believe you have a problem with me pushing you." So I think to myself that this guy is just a real a-hole, and I say something like "a55hole" to no one in particular. Then the door opens up and the guy says "F--- you" so I say "F— you. You could be civil" and then he stands there by the door till the train leaves saying over and over "you want a piece of me?" Like, what is up with that? He looked normal, but apparently was just some sort sort of psychotic animal who had a bad day.