If the tubes are slightly swolen on the left and you have ball pain, it could be a varicocele. Thay are most common on the left. I have one of these. I wrote a post here with an exercise to ease the pain:
marky777 - Severe injury
You must go to the doctor to get a diagnosis though. I am lucky in that the exercise seems to completely manage my condition, and I only have to do it once or twice a year now.
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