My testicles hurt if I do to much masterbating. It will hurt for 24 hours. Then it will go away. I notice If I masterbate to much, I can see just a little blood in my sperm. If I wait about a week to masterbate, I will not see any blood. Sometimes my testicles will not hurt either.I have been this way aleast 10 years ago. I am now seems to give it more atention since it seems to hurt more often . I'm 43 years of age. I will see a doctor soon to stay on the safe side.