I have mild pain in my pelvis on and off since 3 months...i did not even consult because it was very mild. However i get pain when i drink too much water and it sometimes hurts unless i urinate. I can feel that pressure and pain more now. I got my blood tests which were normal. Urine had +1 rbc. Urine culture had no organisms. Could this be stone.?  i am 28 yrs old male. There is also sometimes pain in the back when i sit and study. The back pain comes and goes