Why would my crush be rude all of sudden?

Anonymous
So this guy that I have a class with is confusing. Okay so maybe he has a girlfriend, he walks with this girl but on on social media he says he wishes he had a girlfriend who played Roblox and listen to music together. Before all of this once he put a video on story and it was about him saying he’s tried of everything and him being sad, and I said bruh are you alright? And he answered L M A O no. Why was he laughing. Anyways that ended and he became rude. Whenever we get to 1st period together he would hold the door for me but this time he opened the door for himself and the door shut in front of my face. Just saying he’s giving me looks that look like they hate me but seems nervous. I don't know what to think about this. Is he mad I probably friend-zoned him I don't know. What do you think? He has a girlfriend I think maybe they’re dating, but why would he always look at me and be nervous and so mean.
Why would my crush be rude all of sudden?
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