Whats wrong with my dog?

Question
My dog is pregnant and has been acting fine,then today she became too weak to walk,her whole body is shaking,she won't eat and she is producing large amounts of saliva.what could be wrong?

Answer
This is possibly a medical emergency. I would get her to the vet's right away. It is possible that she has calcium tetany, or milk fever. Drooling or salivating is a sign of it as is the weakness.
She is at serious risk and so are the puppies.
You should get her into an emergency vet.