pain in testicles, lower back, and stomach

[runthescales]

Hi,

When I run/jog or work out hard for more than 10 minutes, I begin to experience a dull ache in one or both of my testicles, which then develops into sharper, shooting pains for up to an hour after I have finished running.  About a year ago, my doctor diagnosed me with Epididymitis (swelling of the tube on the back of the testicle) on my right side and I took Ciprofloxacin (500mg twice a day for 10 days) and the very severe pains went away.  My doctor also said the pain in my lower back when I run might be due to sciatica - swelling of a major nerve that runs from the lower back into the leg.  He told me to take ibuprofen after my workouts if it still bothered me, and I've been doing that off and on.  But still, most of the time when I run, I continue to get the dull ache and it usually develops into tenderness in one or both of the testicles.  It doesn't matter whether I wear breifs, boxer-briefs, or boxers.  Running is supposed to be good for you, but it really is getting to the point where it almost doesn't seem like it's worth it.  Also, I don't want to do any permanent damage to my testicles or other reproductive organs, because this really seems like it's something that shouldn't be happening on a regular basis.  Does anyone know what could be causing it, and if it can be caused by something by sciatica, and if it can cause permanent damage?  Thank you for your help!  

--John, 23