Glad to hear. Sounds as if your snake somehow got it's airway blocked and couldn't dislodge the mouse for some weird reason. I say this because not too far back I had a green tree python go through the same motions you describe, and it didn't end well. Turned out it had got some substrate down the glottis and couldn't get any air, and it was too far down for me to do anything. No way to get it to a vet in time. Sounds like yours may have had a similar issue, and if you hadn't removed the mouse when you did you probably would have lost him. A vet trip would probably still be a good idea.