I think i may have bv i am too young to go to the doctor alone. mom doesn't know i'm sexually active. are there any over-the-counter treatments?

No: You will need to tell your mom you are having symptoms--urinary / vaginal / other and need to see your dr. Then ask to be seen in private so you can discuss concerns w/dr. It will likely be wisest to discuss with your mom so you can be sure to have access to condoms (or birth control pills--but they do nothing to prevent stds, as you have learned).