WHY? im 13 and im losing hair:(?

ok so im 13 my hair is pretty long its 3 inches away from my elbow.i dont really straighten my hair but i do use a lot of mouse and hair gel spray. idk if my hair loss is due to stress because on tuesday we are doing the cst tests at school and im really nervous or it could be that i dont treat my hair right. my moms hair is naturally curly but mine is frizzy wavy and thats y i use a lot of product ... i cant wear my hair withought gel. ...HELP? :'(