Why is my Eastern baby box turtle's shell soft and she is lethargic?

I have a 3-6 month old Eastern baby box turtle? Lately I have noticed her eyes closed and she is moving slowly. I hope she is okay. I have on 1 side peat moss & cypress mulch and the other side shelf liner. She has been eating roaches , red wrigglers, and meal-worms. This is been going on for about 24 hours as best I can guess. She is in a 20 gallon with a 100 watt regular household bulb and UVB bulb, SHe has fresh water and greens daily. SHe is usually bright bubbly and moving about. Her shell seems soft to the touch. It always has been on the under side. SHe has 2 hiding spots and she is misted daily. Given a soak weekly? I am awaiting a MVB bulb in the mail in hopes this works better. I researched the sphagnum moss bedding before using as this is supposed to hold moisture better. I purchased him on 1/2/11 from Turtles Inc