Boston sneezing ; reverse sneezes ; backwards sneezes;

Question
I have been given a Boston 5 days ago rescued after being ill treated he is approximatey 2 years old very loving but when he gets stressed or exited he has a coughing fit: is this normal or should i get him checked out by the vet?
Thank you Chris

Answer
canine choking?  how about reverse sneezing :

Hi Chris,  Many things can be going on here.... Have the vet check him out:

Also, he may have backwards sneezes:

see here: this explains it all:

http://en.allexperts.com/q/Shih-Tzus-3351/2009/3/breathing-Ask-Pet-Nurse.htm