Horrible sound....extremely worried..please help

Buckie has been having dental issues For the past several months. We have gone about every month(sometimes more) to get his teeth filed. he has some root elongation in one area..i know its only a matter of time, but I've just tried to keep him comfortable and happy as long as possible. He has been on critical care for a while now and a little metacam daily. But today he started making these awful sounds. They're hard to describe even. But I have a video. It's super dark so you can hardly see him but you can hear him.


http://youtu.be/VLbaBSDAgbU



Sort of similar to http://ift.tt/1pVXFHk

Any one have any ideas? Tomorrow is Sunday unfortunately so I don't know that anyone will be at his vet. Monday will probably be the earliest.