Male friend flirting?

So, I have this male friend that I met because of classes. He is my classmate and doing exactly my program so we got a bit closer as we help eachother with keeping up with assignments and stuff. He has a girlfriend that I met few times, she is great and I also have a boyfriend. I'm in a long distance relationship so my boyfriend is not always around. The way this friend talks to me feels to me like flirting than just friends conversation. He says things like "I missed you today, your smile makes my day, you make me nervous, I can't wait to see you, why is ur camera off today (zoom classes)". He also watches me a lot and notices everything I do. Like he once told me "why do u play a lot with ur hair during the lecture?" Am I overthinking it or is this normal? I asked him before about this and he said we are good friends and that's how he treats good friends, but then he also talks about how lucky my boyfriend is to have me. This is getting unconfortable to me as I really don't know what's going on. I have him in every single class so I can't avoid him and I'm just trying to figure out how to go about this.