I'm Up About Three Times From My Sleep Needing To

I'm up about three times from my sleep needing to urinate. Plus when I attempt to pass urine, it takes me awhile to pee n it is a weak stream. I went for a prostrate exam n a test that required me to drink alot of water for and I couldn't get the test done because it hurt so bad to hold water that I had to go n try to void all that liquid. But when I tried ...again it was slow to start n when I bared down to pee... I thought I would pass out. What can cause this?