Well Kim only you will really know if he's that "off" that he might be sick but if I found one of mine in behind the hide with the head in an S curve like that I'd read "hungry snake". Many of mine sort of learn to use their hides as cover in many ways....lurking from the doorway, sitting on top of the hide striking downward, darting out from behind the hide to nab dinner. They do use different hunting methods and seem to adjust and change those a bit as they mature and learn to use all of their environment to be a successful predator.