Gosh, I don't know if it's "normal" to have them all at once, and I've not heard of it being done. That doesn't mean it hasn't been done tho.
I didn't' have very good experiences with my myelograms. They were pretty uncomfortable, and they were of the lumbar spine. I lost control of my legs and that was pretty scary, cause I didn't know if it was permanent or not.

Obviously it wasn't, but the neuro was pretty concerned at the time and that put ME in a panic. I'm sure it was just MY reaction to the dye and nothing you need be concerned about. It's not a normal occurrence so don't worry about it, okay?
I'm sure you'll be okay -- I don't know for sure why they're doing them all at once, but obviously it's because of the severity of your symptoms. They need answers NOW, and don't want to wait. When you lose bladder function, time is of the essence so it doesn't become a permanent thing - and I'm sure that's why they're doing this the way they're doing it. So just trust that they know what they're doing.

Let us know how things turn out, will you? In the meantime, we'll keep you in our prayers! God bless and please take care! Hugs, Lee