Blood in urine

I am 18 years old, i work out and eat pretty healthy.
I also stay very hydrated. one day I had brown urine and didn't think much of it I just thought i might have been dehydrated so i drank some more water. it seemed to go away and i had normal colored urine. it's occasionally dark. and from time to time i do see blood in it again. i have been to the doctors and they've ruled out all chance of infection stones I've even had a ct scan.and blood tests. everythings come back negative. My urine will be fine for a month. then one day one time only it will be brown or red. I'm having lower back pain, hip pain and leg pain. when i ejaculate it seems to be thicker than it used to be as well. i also have 2 benine cysts on each testicle only a cm each though. if anyone can help me out and give me an idea on what to do I'd be greatful. Thank you.