With the sleep - Usually I hit snooze for an hour in the morning, but since I started the Master-Cleanse (I'm on day 9 out of 10) when I'm up, I'm up. Guess that's the opposite of insomnia, but sleeplessness in a (beneficial) sense.
As for the tongue - the burnt feeling might be the coating - my tongue has been pretty thickly coated the past week and is just now looking like it might thin out before I stop.
Also, I often get tension headaches and headaches when I haven't eaten in awhile - after day 2, my headaches disappeared completely! Just stay hydrated and you'll be fine.
Congrats on getting to day 7 and good luck on the rest of your cleanse!