I had surgery on an umbilical hernia. I was having a hard time urinating after. The surgeon told me to stop taking Vicodin because it might be causing urine retention, so I stopped. My urination got better by the 3rd day or so. By the 3rd day, my scrotum swelled up, and I noticed that my penis shaft is bruised. Now, my left testicle is enlarged. I’m just wondering if the surgery may have prompted testicular cancer signs. I’m very worried; I don't know why my testicle is enlarged.
I do a search on the internet about enlarged testicle and I’ve found possible causes: cancer, testicular torsion, inguinal hernia, epididymitis, hydrocele, and varicocele. All causes need to be evaluated as quickly as possible. If his testicle is as large as you have described then it should be examined especially if there is a large difference in size between both his testicles. I suggested that you go to the doctor that operated you and yell him what is going on.