YAY! Welcome to the black milk club. He looks like he may be going into shed. (Either that or the camera dulls his colors) so that could be why he's hiding so much. Mine only hides when he's in shed. Otherwise, he sits on top of the substrate with his head sticking halfway out into the open.

Mine is also very skittish and wiggly, though he's gotten better since I've been handling him. He calms down once he's been in my hands for a minute.