Bladder infection help

Ugggg!!!! I had one last week! I am clean. I pee after sex to avoid infection, I wash. What am I doing wrong!!! It is so bad I am fine one second and the next doubled over legs crossed like I was about to pee all over myself. And i feel that if I moved I would pee all over myself. And when I do pee it's as much as it is when you don't have to pee and you try to make yourself go. Sense the first one I stopped drinking pop.  My ob /gyn isn't in till Monday. And I have no money for cranberry juice cause I'm waiting on my new bank card. Help please, thanks from a miserable women. Also I am ten days late with a neg test at  3 days late. Could this have anything to do with it? Makings a blood beta test on Monday