I wouldn't put anything past these guys! Did he seem panicked when he couldn't get in his hide? I wish I could give you a definitive answer, but the best thing will be to wait and see... Try feeding him again in a few weeks, and if he regurgitates again, then take him to a herp vet. In the meanwhile, if you've noticed any strange behaviour, keep a record of it just in case a vet trip is needed, and it never hurts to double check heat and humidity! Hopefully though you're right that he just stressed himself out by not being able to squeeze through his hide opening!