Well you already have an idea....stuff coming from the mouth and noises normally IR. How severe cannot be told though. Some are cleared up at home, but yours sounds worse off although I am NOT a vet. Nor is anyone else here.
As for her runny poop that might be another sign of trouble depending on exactly whats going on.
With all we dont/can't know, I had to give a generic "go to the vet" answer.