Do i like him please HELP?

when i told my cousin that i liked this boy in martial arts,(she goes there 2) i startted to like him more and more. i didnt like him and i wasnt nervious to talk to him or nothing b4 i told her i like him. now, i dont really talk to him, when he comes near me, i get nervious and i sortof start to sweat and one time i started to cry for him and when im at my class at martial arts, i get happy when hes their but when i go home, i get sad. my cuzin and brother tell me what he saya about me and if i leave early after martial arts he starts talking about me but if i dtay until its closed he talks nothin about me and i inlove or something please help no mean comments also he says he likes me ALOT and he would go out with me but he has a girl friend and he doesnt want to be a 2 timer hes not a jerk tho