Stupid for belivein he could be serious bout me.. :/ advice?

so i met this boy at a house party and exchanged numbas and stuff and found out theres a 3 yr difference. but he honeslty doesnt care and said he still wanted to get to know eahcother. talked for days and then last night he stopped relpyin. so i sent him another like " if u dont wanna talk anymore just lettme know." then another one "its not that serious just let me kow wats real" his reply " :( " and wont text me back dsince then. its been a whole day and still nothin. wat should i do? he makes me happy...