Disgusting Tongue
My husband and I both had this after surgery. No black spots, but mine was kinda brown and it seemed like my taste buds were "longer" than they should have been. It was nasty! I was even googling "hairy tongue" because I thought that's what it was.
I think, though, that I finally determined that it may have had to do with the fact that we were on liquid diets, and hadn't eaten anything solid that would help "exfoliate" our tongues. Or, it could have to do with being in ketosis. At any rate, it didn't last, and finally went away on it's own. I say mention it to your doc, but don't worry about it too much in the meantime.
I think, though, that I finally determined that it may have had to do with the fact that we were on liquid diets, and hadn't eaten anything solid that would help "exfoliate" our tongues. Or, it could have to do with being in ketosis. At any rate, it didn't last, and finally went away on it's own. I say mention it to your doc, but don't worry about it too much in the meantime.