Definitely aged 12 for me, early puberty.
Prior to that I had issues, I was a bed wetter and had UTI infections. I had regular checkups with my nice elderly male doctor who examined the head of my penis, no further. He prescribed antibiotics and “the yellow ointment” with follow ups when required.
I did not have shyness of the examinations from that doctor till that point, they came all so often. He never examined my testicles only my penis. I was extremely shy of others seeing me naked, we had communal showers by then, I was the youngster of the class.
By aged 12 I visited the doctor’s surgery alone for the checks after school. I had stopped wetting the bed but was still getting the examinations every few months.
What happened that day was totally unexpected by me.
He examined me down below as usual, but said it was time for me to have a “test” which in his opinion should only be done by a female doctor. He actually asked me for my consent, a first, I felt so grown up, I consented.
He phoned through to a lady doctor who led me through a side door to a narrow completely empty decorated room.
She stood facing me and had me do breathing exercises whilst examining my testicles by massaging them as I stood fully clothed with my legs apart and trousers and underwear dropped to my knees. As she did so she talked gently to me, “relax”, “focus on your breathing not what’s happening down below”, “this is not going to hurt” etc. I became aroused, she stopped massaging and held my testicles until the arousal subsided.
She then back turned and left the room, I got dressed and went back through to my regular male doctor. This was the first time I can remember being embarrassed with him.
He told me that I didn’t need to come back for the urinary issues because I had taken an erection during the test. I was now developed enough I would not wet the bed. He said that when he had examined me at a previous visit he had seen some hairs, so perhaps this test was a little overdue. The thought that the two doctors had been discussing my arousal felt so embarrassing.
I often wonder if this test was necessary, couldn’t the male doctor just have asked me if I got erections? Seeing is believing?