Please help! My wrist hurts so bad!!!!?

I was cleaning out my attic today and I was pulling and tugging and lifting really heavy boxes(I'm a 14 year old girl) and I have some back problems too. It really hurts to bend it back and forth and I don't really know why it is hurting. Bending it palm down hurts the most. But it hurts like he'll itself so can some one PLEASE HELP ME!!!