Receding hairline and still young.Solutions?

I started noticing my receding hairline about two years ago. I know it's not heredity because my relatives still all have a head full of hair. I know for a definite fact that the reason behind this is due to the fact that as a kid I used to tie my hair into a ponytail really tightly. I've lost about half an inch, but it's stopped receding now. I'm probably blowing it way out of porportion than it really is, but I still would like to know how to get that hair back. Girls...any solutions?