Hey all im 14 and I currently havnt been gaining any weight at all for the longest time and lately ive been developing stretch marks on various parts all over my body. Its really depressing cause im completely terrified of taking my shirt off in public. I suspect its cause I have bad genes or something. Cause I got alot of em now and its really saddening. =( So what I want to know is is it genes or something else? or what? cause I havnt gained any weight or anything so im stumped.