Suggest Medication For Infection In The Vagina

I got fingered last Thursday and the next day I experience a lil pain. That's normal.Two days later I had some Yellow discharge. I doesn't Stink or smells Bad. When I wipe my vagina it sting but now it seem like it spread to my Butt because when I wipe my Butt it stings too! Also when I wipe Brown specks get on the toilet paper, just from my vagina tho. I was thinking a rash, and I was just going to get rash cream.