it could be a CT, does the cough sound kind of raspy and does he hack at the end? have your vet check, and be sure to have him do an x-ray, then have a good look at the trachea.
Even if the coughing/wheezing stops, CT is a chronic disease, so its better to check to make sure. Better to know now before something happens worse in the long run right? But good job on watching over your puppy and trying to relax/calm him whenever he started an 'episode'
also here's what my dog sounded like with a CT (its a video that I put up in another thread)
http://www.dropshots.com/day.php?use...1&ctime=144216