I can’t remember if it was the exact same procedure, but I’ve had something very similar when I had a bladder biopsy done, but I’m going to beat you on making someone else uncomfortable :D

For anyone who doesn’t know, these procedures start with an anaesthetic gel being squirted into your penis through a syringe to numb everything, then the camera and tools get inserted. It’s been a while, but from what I remember, some air gets pushed in along with everything else. The nurse warned me that the air coming out can be uncomfortable. I also had to have a pretty full bladder for the procedure.

Afterwards, I needed to pee straight away, so used the toilet next to the waiting room. When I went, it burned a bit from the gel wearing off and everything just generally being tender. Suddenly though, I had this feeling of intense pressure, and a fireball forced its way out followed by some boiling pee. I used my free hand to steady myself, and my knees almost buckled. I let out an involuntary ‘Jesus Christ!’. I finished and cleaned up, and the nurse met me outside the door.

She had a huge grin on her face, and said ‘I told you it would sting’, then nodded towards the waiting room, where about half a dozen terrified looking men had apparently heard me :D