i'm new to taking care of hermies, and my newest that i just got about two weeks ago, sheldon, was very active the first week, but now, all he does is bury himself in the sand all day and all night. i've seen him out once and that was two days ago, and it was only for a couple of seconds. ould something be wrong with him. could he be sick, or depressed? or molting? and if he is molting, how do i find out and take care of him?