I have had a similar problem/problems. I though traced the origin back to a surgery I had a few years ago in an unrelated area. For some un known reason the surgeons were in that area in my case, I am still today suffering from this and I simpathize with you greatly. Perhaps you had some surgical proceedure and the peripheral blood vessles were damaged in that area or perhaps you inadvertely hit or compressed the blood vessles in that area and they are damaged. I would try a heating pad and some vitamin E therapy it may help. In any case good luck
I get this too , did you ever find out what it is ?
I would see a Urologist and make sure they check your prostate