Yeast Infection?? S.O.S.

I'm pretty sure I have a yeast infection, and I don't know what to do about it. I don't have anything to treat it, I don't have any money, I also can't get to the doctor. What do I do?? My period starts in 5 days, and I start school in a week or 2. It's so itchy and irritating. Please help!