This is a great article on upset stomach in dogs and home remedies to try along with advice on when you should see the vet from a former animal hospital assistant.
if your dog is ill you want to make it feel better as soon as possible because no one wants their pet to suffer for longer than the necessary amount of time to figure out what is wrong and to make it better. Adrienne Janet Farricelli shares loads of info on Hub Pages to help you first to determine if your pet needs to see a vet right away. If it is not an emergency then she helps you try to figure out what might be the problem and how to go about trying to make it better.
She shares videos that will help you determine if the dog is dehydrated and what to do if it is. Then she discusses fasting the dog to slow or stop vomiting and then to re-start feeding with a bland diet that she tells you how to make. This is great information for anyone that has a dog or multiple dogs.
It may be that you can follow this advice and avoid a large vet bill or at least make your pet more comfortable over a weekend while you wait for Monday to see a vet. It will also give you an idea of which symptoms to not try treating at home, so you can know right away if your pet needs professional help and you can get to a vet before the dog suffers more or get worse.