Hello, my first dog is about 6 months old, a Jack Russell/Shih Tzu Cross. Last night we were in the park and he started coughing and exhaling really quickly through his nose. He was shivering violently on and off (not all the time), and rubbing his paws against his muzzle. I immediately thought he was choking, and so did the same things I would do if a child was choking. Nothing came out, and I checked his mouth and there didn't seem to be anything there. He seems, off and on, to be rubbing his tongue repeatedly against the top of his mouth, and again today while in the house, he started shivering for a few seconds, rubbing his paws against his muzzle etc. I can't see anything in his mouth, could it be something to do with him teething? A tooth fell out a couple of weeks ago, and he's started chewing my wooden chairs... Don't want to take him to the vets and get charged a million pounds to be told it is perfectly normal. By the way, he's not unusually quiet, whining etc, seems normal apart from when he's doing the really disturbing thing!