ahh you’re wonderful, thank you! just doing some quick searching around and someone mentioned if it’s near time to do a complete cage clean it could have an effect? i don’t see how since i spot clean and don’t see any signs of mold, but tomorrow is actually cage cleaning day for him (it’s been a month), so i wonder if maybe that’s it? he’s relatively new to aspen, so maybe that is also affecting him somehow?
i normally cycle him between substrates every cleaning as a bit of enrichment. he goes between aspen, paper towel, and carefresh. this next time i’m thinking of trying eco-earth since it’ll be easier to maintain his humidity (and once i no longer need to have my heater on i’m thinking of trying reptibark, but i know it’s supposed to be awful at holding in humidity so i don’t want to use it when my room is dry). should i maybe nix the aspen? he did fine with it last time.
the urate was also right next to the hide he was in, so i suppose exposure to ammonia is a possibility? but it couldn’t have been there for very long, as i checked his enclosure last night (though admittedly not this morning- shame on me).
another possibility is stuck shed around his nose. he shed poorly last time around (i was out of town and his humidity was around 50% when i got back, but he had a humid hide the entire time i was gone- so he had the option to be in a humid environment), so it’s possible something is stuck there. i didn’t see anything, but i’ll check him again tomorrow.
the last thing i can think of off the top of my head is that i cleaned my heater’s filter earlier this week, but as you said: bps don’t have a diaphragm to sneeze from something like upturned dust.
everything i can find online talks about repeated “sneezing” noises, and his was only once and hasn’t happened since, so i don’t know. can a snake “startle” itself awake? because i’m 90% sure he was sleeping right before it happened. i’ve never heard of a snake doing so before, though. i also might’ve accidentally touched his head or something, startling him awake- so it could’ve actually just been him huffing in annoyance (i had been messing with his head earlier to see if he had stuck shed on his head boobs, so he might’ve just been fed up with me)