dude did you already go to a doc? When i was like 14 i had this ball pain and the doc made me do some exams because there was the possibility that some of the vessels that go to the ball got torn and it could necrose (yeah!). It turns out i was just masturbating too much ehhehe but the possibility exists.
btw, it is the most strange feeling in the world having a man touching your balls.
As a kid I've had http://en.wikipedia.org/wiki/Epididymitis ...it came with the most indescribable testicle pains ever, at its worst I couldn't walk. Went to a doctor, got antibiotics and got better really quick.
I have Pelvic Inflammatory Disease so every pain in the entire region has occurred. Over the past year or so I have had extreme pain in that same region (the Epididymis), and its always there to some degree, even now, just sometime it can get really bad to where I can't walk. After and MRI, having my junk felt up more than once and a prostate exam all they can say is that I am perfectly fine but considering the pain I am in, looks like its just a case of chronic inflammation. Ibuprofen helps a lot.