Well I have noticed the other day that murphy would be heaving a little bit in the morning, even seems like he throws up in his mouth a little and then swallows it again. This morning it seemed even worse, he threw up a little in his crate. After he eats and gets out for a few minutes, he doesnt do it any more. This morning after he ate, he didnt drink much water. I had to hold it in front of him and splash my hand in it and he only drank a little bit. Other then that he behaves like the normal high energy dog that he is. His stools are normal, not runny or anything. I was waiting a couple days to see if it got any worse, and I am pretty sure I am going to take him to the vet soon unless someone can shine some light on it.
I'm not a vet and I would consult one no if it continues no matter what is said on here, BUT it sounds like Kennel Cough maybe. When Mocha had it she made a hacking sound almost like she was gagging on something. I only heard it in the mornings when she first woke up. She had been vacinated so she didn't get a bad case. I know some dogs will actually throw up if it's bad enough. They can also have a runny nose. If that is what it is the vet may give you antibiotics or they may just let it run it's course. I think others have said you can give regular Robitussen.