Does He Like Me? HELP!!?

Hi, there is this boy at my school, i really like, and spoke to a few times but now, a few months later, whenever i see him in the corridors at school, he says hi, but avoids eye contact and looks at the floor, i don't think i've done anything to make him feel uncomfortable in my presence, so may he like me to? and if so what should i do? i need to be discreet as i don't want the school 2 know, so please help! (i was thinking of leaving a note in one of his musical instraments, he leaves them near my registration every most mornings when he has lessons-he's so musical!)