That is ridiculous. You should be able to schedule and appointment for any reason without explanation. I did encounter and embarrassing situation where I had a boil down there, and scheduled an appointment to see my Primary. No questions asked. When I got to my appointment, the nurse wanted to ask a bunch of screening questions about my visit and I just said "It's personal." She accepted that.
I personally, would avoid Black Cohosh for several reasons. It is known for side effects. It is an unregulated herbal supplement, which means purity, quality, and concentrations are not monitored or regulated. People have had dangerous reactions to it. Fire your GP for making such a recommendation.
I was told that the key indicator with the PSA test is not what level it is at. It is the rate of change in levels over time. A rapid increase is the warning sign. Mine has been undetectable too for many years and I am 68. I think seeing the Urologist, especially one well-versed in SRS is the smartest move.
Hopefully, it will be an easy fix. Good luck.