Welcome to YT
!
Do you know what a reverse sneeze sounds like and could it be that? Here are some samples, see if it sounds familiar:
http://www.yorkietalk.com/forums/die...d-trachea.html
What did you try to 'calm the stomach'? Bc it does sound possible that it could be reflux. When he's having an event, does he also swallow a lot and/or swallow harder than normal? If yes, that can sometimes be a sign of reflux too. If reflux is suspected, Reglan might be worth a try.