I am sexually active and have notice a sensation, or discomfort in my right testicle. I have felt for lumps linked to testicular cancer and found nothing. It seems like it more of a sensation then pain, almost like I know I can feel it but it is not making me hurt. Also, when I ejaculate, I have a quick sensation once again in my right testicle and then it dissapears within approximately 1 second. This also doesnt hurt, it is more or less a quick, abnormal sensation I feel directly to my testicle. I have had a girlfriend for over 4 years, and have only been with her, so I can confidently rule out any std's. When I ejaculate during sex, there is no pain, only when I masturbate. What could this possibly be? Thanks!