is epididymal hypertension (EH). The blood vessels to the penis and testicles expand to make room for increased blood flow, causing the penis to become erect. This increased blood flow subsides after an orgasm.
is it normal for the bottom of your back to hurt when you carry on masturbating after you have ejaculated? recently my testicles have been aching on and off for a while, i think i have pulled a muscle in my groin but why would that hurt the testicles?