Answers: At your age, I would have to guess a bruise base on your previous physical activities, or possible testosterone build-up if you haven't have a sexual release in yesteryear week. However, there are cases of testicular cancer surrounded by men your age and nobody on byedr.coms is qualified to practice medicine over the internet. I can't quality your pain and your the one who have to decide if it warrant a visit to your MD.
I don`t know its aftermath lol