Is it normal to feel this way?

Theres this guy I like and stuff. He is moving away and is also straight (I'm gay) He doesnt know I like him. Everytime I think of him i feel a viceral pain In my chest, it's not unbearable. I REALLY like him. If you were talking in Twilight terms, I'd be Imprinted on him. I can't stand to be away from him. I am always on the werge of crying but i never do. So some advice?