What is the cause for swollen testes?

Q: I have a problem one of my testes is slightly swollen. Let me give a short account when it happened.I usually masturbate frequently , once after masturbation after some time i found one of the testes the right one has swollen and it was slightly paining.I just let it for one day the swelling automatically subsided.So i did not bother about it too much.But now i have a doubt after the swelling is subsided still the right one is slightly may be some 1cm bigger in dia than the left. Now after this has happened whenever i masturbate i feel a pain in my testes , other than that i feel like iam urinating frequently.So please guide me in this issue as to what is the problem and what should i do to cure this.

A:There is a possibility of potential for twisting of your cord (torsion) which must be getting aggravated during vigrous movements during masturbation. Better get your self evaluated by a urologist.