For what it’s worth here’s my 2p’s worth.
As a young adult I had frequent painful and tender testicles, mostly one side but occasionally both. The pain sometimes extended into the groin. This would come on over the space of a few minutes often as a result of walking or running. As a young lad the thought of this occurring curtailed many of my activities.
I saw a number a number of specialists who prodded and poked for the conditions posted above but to no avail.
I began to notice a correlation between the periods of pain and having a steady girlfriend. There was no doubt that while I was ‘getting it regularly’ the pain would not occur. Likewise, in the absence of a girlfriend I could take the problem into my own hands, with the same result. Eureka, why did it take five years to find this?
Clearly this was a build up of ‘back pressure’. I still don’t know if this is a known condition. Do some young lads over produce?
If this helps one person it was worth posting.