What are you controlling the heat pad with? You need a thermostat. What are the hotspot temps? Randomly climbing/exploring is normal. Wait about a week before you offer food again. Nose scraping could be a sign of him starting to shed. I dont see any problems other than the fact you didnt list a thermostat as one of the items you have, its argueably the most important thing in keeping reptiles, If the hotspot get too hot its dangerous and can burn the snake. Just out of curiosity what do you mean by sawdust like substrate?