Gosh, I really think your dog sounds poorly. Not a good sign when they don't eat. To put your mind at rest as to what is wrong, you should take her to a vet, otherwise you will just keep worrying.
Let me kn ow how you get on.
ALEX PLEASE GET HER TO THE VET AS SOON AS YOU CAN AS IT MIGHT BE CATCHING TO YOUR OTHER DOGS.
WHATEVER IT IS YOU MUST TAKE HER IN AS SOON AS POSSIBLE.
Please let us know the outcome.....sorry you cannot fix this yourself.Read other posts on here.