Why would my testicle still hurt after being hit hard a year ago?

Chronic pain. Testicular injuries vary from mild bruising to complete rupture where the lining that holds the testicular tissue breaks. This can set up a severe inflammatory reaction that can lead to bleeding, fluid build up and, in extreme cases, loss of the testicle. A scrotal ultrasound can help see if any of these possibilities apply. Some men develop chronic pain from testicular injuries.