Help! My dog is sick, I have no idea what this is! We ARE taking her to the vet but they aren't open today.?

You are right, dogs do not get Chron's disease. However, a vet visit is a must, it can be anything from parasites to suden diet changes, or even exposure to poisone or toxins. Dogs do get bouts of gastro enteritis, you can read more about this disorder below: