Update: Can't seem to find an edit button, so posting this as a reply. I understand the weird behaviour I recorded can be attributed to shedding. This is a huge relief. However, he seems intently focused now on burying himself as deeply as possible into the substrate, to the point where I had to spend ten minutes actually digging through it to find him to try and coax him to eat. He refused his food this evening, and I'm still quite worried... I had to feed him mealworms for a couple of days because they were all I had for a while. Haven't found any poop recently, and I'm worried about impaction...