I am a preloader and latly have been feeling very dull to sharp pains in both my right kidney and well as my right testicle. I was convinced i was having another kidney stones as they were similar pains from one i had a few years ago. Anyway after work yesterday i could barly stand in pain in both parts were killing me and i made it through my shift and finally decided to go to the ER. After a CT scan showed no stone they took an ultrasound of my testicles and later told me i had Epididymitis they DR told me that with this particular job constant heavy lifting can push urine back into the epididmis. As most preloaders will know we are always busting our backs with a full bladder not stop one package after another me personally load 5000-6000 packages a week with an average weight of 20lbs thats 100000-120000 lbs a month!!! Never mind per year Anyway my question is has anyone every experienced this or have similar pain in there kidney or nuts?