How To Treat Yeast Infection In Vagina?

Hi im vanessa lately, my vagina.. has been itching Excessibly. I mean, it doesnt hurt itj ust CONSTANTLY itches, and i'm only 14 i have no had sexual intercorse, i do admit I do masterbate, does that have an effect? My vagina itches, very badly. And i'm getting worried, because i feel like i may be getting a yeast infection, and i doubt its that serous. but I always take percaution.