STD INFECTION ? MASTURBATING ?

hi so im 12 years old. I've been masterbating for a while like 6 months ? and i cant buy any toys or anything, so i have this big brush. the handle is round and i materbate with it. and when i *** it gets on the brush. i sometimes rise it with just water or pass a wipe to clean it. but a couple weeks ago every time i peed uit really burned. now it doesnt , but i have this white discharge in my vagina , and my pee really smells. is this an infection ? or an std ? i dont have any bumps or anything in my vagina. is everything ok ? im really paranoid! lol help !