Not a clue. For me, it doesn't mean much, except annoyance. I get the barking cough a few times a year (I always liken it to a seal). It comes, it's irritating, it tears my throat apart, and then it goes. *shrug*
As for the pressure thing, I get that too sometimes. It doesn't always go with the bark, it often comes on its own. It's annoying, and it goes. Sorry I can't be of any help.