I Was Put On Flowmax To Help Pass Possible Kidney

I was put on flowmax to help pass possible kidney stone. It started with a pinch while urinating and alittle blood afterwards. But since being on flowmax I am peeing 3-4 times a day and when I take the pill at night it seems to keep me from urinating atleast until the morning. I developed constipation today is all of this normal. I'm freaking out that I might have bladder cancer. I'm 34 yrs old