Hii Doc. I M 22, Actually Whenever I Try To

Hii doc. I m 22, actually whenever i try to masturburate urine comes out. I don't know what's the problem??
And one more thing whenever my penis erects nd I try to masturburate, sometimes blood starts flowing in my the blood vessels of anus. I start feeling a little pain nd it seems that if i don't stop at that point my veins of anus would burst!!