ADVICE PLZ! should I go for it

Okay I posted this is another group but there's not many people in that group. So I'm 16 and I'm crazy about this guy that I have a class with. He's WAY out of my league, but he talks to me for the entire hour everyday. I flirt with him and I've told him he's perfect and he has pretty eyes and other blunt stuff. He occasionally says flirty stuff to me, but he never seems bothered by me flirting with him. Although once I did ask for his snap and he was not down and I was super embarrassed. My friends and even my mother think I should go for it but I'm terribly afraid of embarrassing myself again. I have a few days left before our schedules change, so no time to waste. What do I do??? I DEFINATELY will not be asking him out, but I was thinking about saying like "this is gonna sound pretty weird, but promise you won't judge me: I really like talking to you. Idk if you do or if you're just being polite to me..." Should I do it, or will I just get turned down and embarrass myself. I'm leaning toward doing nothing bc I'm kinda fat and not attractive and I don't understand what he could see in me