How To Reduce Stretchiness And Dark Color Of Vagina Lips?

I am 13 and I am very concerned with my vagina's appearance. I haven't started my period but, I have been having a lot of white stuff coming out randomly. I am not sexually active. My vagina is a dark, almost gray color and it ithes most of the time. It also has very streched out lips that sometimes poke out of my underwear. It grosses me out and I am ashamed of it. How do I reduce the strechiness of my vagina lips? How do I get rid of the dark color? Please tell me.