Help with crush

I think I have a crush on this guy I used to go to school with in secondary. Coz I moved schools for sixth form I haven't seen him in like 2 years but since study leave I've been going to the library and I see him almost everyday there with his mates. I don't want to approach him in person at alll cos I'm too shy and scared. Also it's a bit embarrassing cos if things didn't work out it would be really awkward. I'm in year 13 now but I remember in year 10 one of my girl friends told me she heard from someone that he might have a crush on me but I sort of dismissed it cos I didn't believe it would be true. He's also quite popular boy and I'm very quiet shy loner type haha. Anyone have any advice? I was thinking to wait ti after exams cos then I won't be going to the library anymore but at the same time I don't want to loose the momentum.
Also forgot to mention that as he was getting up from his seat he sort of gave me a half smile but idk if he was being friendl??? ahh pls someone help me out!!