Sounds like you're doing all you can. Is it a hatchling? I've had a few do that in the past, and it is usually not a good sign. Hatchlings have a high mortality rate as it is, and once they contract an illness or suffer a deficiency of any kind, that mortality rate tends to skyrocket. However, I haven't seen your tortoise, so I couldn't say for sure what will happen. Hopefully by now, you've taken the animal to the vet. How is it doing?

T.G.