Why Is My Right Testicle Hard And Sore, Especially After Sex?

Hi,
I've noticed over the past few months my right testicle would be sore after sex. My wife and I would have sex 2-3 times a day. Only after the 2nd and 3rd time is when I felt discomfort. The past two days my right testicle is noticeably hard compared to the left testicle. The pain is at a mild 2-3 but it is very uncomfortable and I know something is not right. The past two evenings I take advil to for swelling and in the morning it feels fine. Then I notice as the day goes on it gets harder and more uncomfortable. I am worried and have to consult someone before I see a doctor. I doesn't sound like cancer and I am not sure what it is. Also, I can remember the day it all started two months ago I was interrupted mid ejaculation that stopped my orgasm and that hurt my right testicle with a sharp pain. I feel that is what has started all of this.. Please if anyone has any suggestions I would appreciate it very much?? Thank you!.