Falling for a younger guy.......?

ok so im a sophmore, the guy im falling for is a freshman. ive never like anyone younger than me, and ive nvr bn in a relationship with anyone. :( im his dancing partner in a quincenera im in. hes seems really nice and seems to have everything i like in a guy. but during the dance in the quince we switch partners and he switches off to another girl, the girl he likes. his sister and a mutual friend thinks he likes me but i cant tell because he seems happier when he dances with the other girl than when hes dancing with me.... what do i do? do i continue liking him or move on?