For some reason I have stretch marks on my thighs. I have been using palmers stretch mark cream, but I'm not sure if it will work because I have had stretch marks since I was 13 (now I'm 18) which doesn't make sense because I'm 97 pounds. So I realized that its just genetic. Is there anything I can do? And I also have dark circles around my eyes I have had them since I was 5 Who knows why? I'm really sick of it Any tips will help.

What is your height?
Consult your doctor about these 2 issues, as they could be genetic or something else, but they could suggest products for you either way.
You could try Vitamin E or Mederma for stretch marks [both used for scars, so you could try them on marks to help fade marks].
Also it is important to take care of the skin under the eye, which is extremely sensative. You should at any age, use an under eye cream, which you can find in the pharmacy or drug-store from a choice of brands such as l'oreal, or revlon, etc. Or other brands like Pro-x which are more professional. Try looking in Sephora, drug-stores, and consult your dermatologist.
Also, if you wear makeup, you could blend concealer under your eye, or try an under eye brightener.