It's a madagascar speckled hognose, a leioheterodon- not a heterodon. There is a considerable size difference between the two.
You've only had him three weeks. Stop draping him around your neck and stop handling him until he eats for you. Make sure he has a deep substrate and plenty of security in that 40g breeder - which mean blacking out three sides if you already haven't done that. Put him in an area with no traffic and stay away from him for awhile.
After you've double checked his security situation, and he still doesn't eat, or he loses body mass, or shows any other signs of systemic disease, then a trip tot he vet is in order.
Uh was that directed at me or OP? Lol I only have westerns. And mine are all 3/4 blacked out and in a separate structure from the main house, no foot traffic aside from maintenance and feeding