There was blood in my urine and I was wondering how serious of an issue it is. It was mixed in pretty evenly and was never just blood. I had just finished masturbating but it was not aggressive and I have not do it excessively (maybe 3 times a week). Also I had a strenuous practice about an 2 hours before. I did not have any pain or any other symptoms of a UTI or kidney stone while urinating and have not had any after or and had none before. What is the cause? What should I do?