Yes i experience the same thing from time to time, lower back pains from one side to the other especially on my left side and sometimes pain in my lower left ribcage i didnt take any blood tests but i did a couple of ultrasounds on my kidneys and bladder and it came back fine....when it comes to the urine part i have had cloudy urine, foamy urine, burning urine as well, it might have to do with anxiety but i dunno i think sometimes it might be something more serious, i put in the symptoms for a search and i got back this website that spoke on overmasturbation and the effects it can have on your body, yet many other websites say there is no such thing as overmasturbtion.