I've had a Ball Python that just decided that she wanted to dig in her substrate for a week or two, then she stopped. Their might not be anything wrong at all, your snake might just be having fun lol. If your temperatures and humidity levels are in the proper ranges, you have proper hides, and the room that your snake is in doesn't have a party going on in it constantly I'd say your fine. I don't think a snake would dig down to try to get off stuck shed, there are far more efficient methods for that. The nay thing I can think of is that you snake might be digging down to try to find a cooler spot. I wouldn't change anything until you can verify the cage temperatures, then go from there.