I think I have a yeast infection...?

Okay, so i'm 15 and I think I may have a yeast infection. Every month for about a week before my period I get this white cottage cheese discharge. Has somewhat of a fishy odor. It burns when touched or rubbed against. Swelling and inflamed also. Not sure what to do. I heard eating yogurt helps. Don't want to tell my parents because I know they'll think I have some crazy STD or something. Is there anyway I can get rid of this once and for all without being prescribed anything by a doctor?! Please help. EXTREMELY UNCOMFORTABLE.