Help!!! Stretch marks?

I'm 14 years old and i have a lot of stretch marks on my inner thighs. I didn't really notice them early on and i got them a few months ago. I bought Palmer's cocoa er with vitamin E. I've been putting it on in the morning and at night for a month and they haven't gotten better. Any suggestions to help reduce them or how long this will take. Summer is coming up and i like to wear shorts and skirts and hate these ugly stretch marks. Please help!