I didn't know that the test I was given was SFEMG, but now I know.
They did it in the muscle under my left eye and the "shock" they give to see how the muscles react was extremely painful (could have just been because of the area the needle was inserted, but I don't know)
I could not see myself but it felt like I was shaking like someone having a seizer.
Not trying to be dramatic, but this was my experience,
My recommendation would be to get what ever test needed to help with your condition.
It only pains when the shock is given, which was between 1/2-1 hour off and on. (didn't have a watch, just making a educated guess)

good luck

randy