How can I treat a UTI without antibiotics?

I am 15 years old, female, and ually active. I have a UTI but I cannot tell my mother or she will know I am ually active. When I drink a lot of water, my symptoms disappear but in the morning when I have to go to the bathroom, they reappear. My urine is strong smelling and it tingles to go to the bathroom, but there are no cramps or additional pain. The last time I had was on Saturday