Don't panic! Bladder cancer is highly curable in the earlier stages. Besides, it's possible this is just an infection that may have got into your kdineys, which could explain all those symptoms. But the cystoscopy definitely needs to be done to determine exactly what's going on.
Do post back after you get the results of the biopsy. I certainly hope it doesn't turn out to be cancer, but if it does, I can give you some information regarding it.