Why do i have sores on my vagina?

I'm 14 years old and I have these white sores on my vagina and it does not hurt to pee but to wipe it hurts like no other.. I'm not sexually active at all but I did masterbate with an electric toothbrush.. it itches and I refuse to to go to a doctor, is there anything cheap I can buy from the store and can anyone tell me home remedies and what is happening? Please I'm scared