My pacman has been burrowed for a couple of weeks. He hasn't been interested in eating either. I uncovered him two weeks ago and he ate 1 nightcrawler then burrowed again somewhere else in the cage. I have no idea where he is now. Is this something to be concerned about? I use coco fibre substrate, have a thermostat keeping the temp around 82 F during the day and 78 F at night.