Ugh! help! desperate!!!?

omg....please hlp! im almost 13, 120 pounds, 5' 6". except i feel SO. FAT. first of all, i dont know if thats normal, to be 12 and 120 pounds!! thats like 10 pounds a year! anyway whats bugging me lately is my stomach. there are like, rolls! ew ew ew. i have never been fat in my life, but ive never been super skinny either. my moms side has genes of being kinda chubby around my age, and im actually a lot thinner than my mom and grandma were at my age. anyway the point: i NEED a way to lose weight. and i have like no self control...any ways to keep control over what i eat? also, whats an easy way to lose a little weight within a few months? and... is my weight healthy for my height and age? thanks sooooo much!