UTI Question?

I have had at least 6-7 UTI's so far this year. I feel like I have a super mild one right now. The last few I've had were like this as well. My last one, I drank water like it was my job, and took cranberry pills, and went to the doctor. According to her, I flushed it out because there was no sign of infection in my urine sample. Can I just do that again? I guess if it gets worse, I'll go to the Doctor, but I don't feel like it is urgent at all. I actually feel normal today. I know that untreated it can move to your kidney, but I think If I keep going with the water, I will eventually flush it out. Also, I hear that UTI like symptoms occur occasionally with Birth Control. Anyone else hear that?