He is a big dreamer. Wakes me up plenty with his little barks and yips in his sleep hehe.
Occasionally my dog got a "funny turn" like this, but it didn't really mean anything in her case. She is fit and well. I wondered if it was some response to dreaming, or like one of those things I used to get when waking from sleep (similar) -waking catching my breath, but physically well otherwise.
However, I would check this out with the vet to be on the safe side.