Honestly, I don't know anything about this. But I'll offer my perspective none-the-less. I believe you also posted this in the sleep issues forum & Thunder Bow replied suggesting you see a urologist. I think, if you haven't already done so, this is a good suggestion.

My personal thinking, with regard to this, is that you perhaps want to have your concern checked out by at least one specialist... perhaps more than one. (Sometimes doctors don't always get it right either.) But if you keep coming up with nothing in terms of any kind of physiological / medical problem, then at some point I think you have to consider the possibility that this problem may be related to health anxiety or something such as that.

Here are links to a couple of articles, from PsychCentral's archives, on the subject:

https://psychcentral.com/lib/ocd-and-health-anxiety/

https://blogs.psychcentral.com/anxie...ealth-anxiety/

Best wishes...