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What you may be seeing is a reverse sneeze if the episodes come on suddenly, last a few seconds to a few minutes, and then end just as suddenly.
With a reverse sneeze the dog sounds like it is choking or gagging on something, and sometimes it looks like they are backing the body when standing.
This is not harmful to the dog and many dogs do this. It is thought to be from possible allergies.
If it were Kennel cough, you would see coughing more when the dog is active and not at rest.
I am going to direct you to an article on a reverse sneeze as well as to a video so you can kind of compare the dog in the video with what your pup is doing. For some dogs it is more dramatic sounding than others.