Sounds like a normal reaction to me. Nerves can definitely give you tension headaches, and turn your stomach into knots.
I’m sure the surgery will go great. I believe it’s a pretty short and simple procedure. I’m guessing your more worried about the test results than the surgery.
How did you decide on what size prosthesis to get? Just by measuring the size of the other one? That wouldn’t work for me because my testicles go up and down in size on some kind of cycle that I can’t seem to figure out. All I know is that they are quite a bit larger at their largest point than at their smallest.
I think I’d need a Pump Reebok adjustable testicle. :)