Weird/awkward situations with your crush?

I had a big crush on this guy and well here's the thing I didn't really know him much- he went to my school, same grade level. From time to time we would make eye contact ot even bump into each other but it never went to more lmao. I get really weird when I'm near my crush, so I got loud and annoying when I was around him. All of that happened for a whole school year, now we both go to different schools but they're right next to each other so it doesn't really if you go into the other building. So this still happens to time to time but I've been avoiding to go the school :') so I don't think I'm over him, but how the hell did I get a crush on someone I don't know that much?!
-z