swelling in my left testicle

Hi i was wondering if someone can help me. Ocassionally after having sex or masturbating i get some swelling and discomfort in my left testicle. Sometimes it only lasts around 3-4 hours and then goes away. The swelling is around the "cords" that attach to my left testicle and then goes way the next day or in 3 -4 hours. I have also got the pain after surfing a couple of times. The testicle also moves by itself when it is swollen, very wierd.

I am not overly concerned as the pain generally goes away and i am aware that testicle cancer doesn't often involve pain.

It doesn't happen all then time, sometimes i can go 6 months without incident. However in the past month i have had it happen twice.

Any ideas anyone??

The blood may be backing up in the veins above the testicles. It is called varicose veins. It is usually not painful but it could cause discomfort.

I would have it checked since it could lead to infertility.