Usually a range between pink-red to yellow-orange with white areas. If you can get some photos I can take a look if you'd like. Usually the concerns arise when there are sores/wounds or if there is swelling along the gums/jaw which could indicate infection.
Mirage came out of brumation on April 26. He was doing great. On May 2 he started acting funny. We just redid his tank, and he keeps going into one of his hides. He just lays there. He shows no intrest in food. HELP!