i cant stop thinking about my crush?! what should i do?

he is always on my mind! i cant stop thinking about him, and overanalyzing anything he says to me. we talk a lot but i dont think he likes me in the way i like him, and sometimes i feel like he doesnt like me at all! for example, on monday, the day after winter break, he didnt talk to me first in class. idk if he was tired or he just didnt want to talk to me. what do you think? also, i go back to school tomorrow because we had snow days the past 3 days, what should i do/say to him? i kinda want his phone number but i dont want to ask for it because im scared of rejection. a week from tomorrow the semester ends so we get new classes. and if hes not in my french class anymore i wont be able to see him! because hes in junior year and im a freshman so we cant have any other classes together besides french. also i feel out of his league, hes older than me and good looking and probably popular(hes a jock, but not the sterotypical meathead). i feel like ill never be good enough to date him even though im pretty, smart and funny (not to sound conceited). i have so many problems with him, ughhhh, what should i do?