Hmm........did the vet do an xray last Friday to determine the # of pups? Xrays are usually done about a week before the due date & if he could see the pups well enough to determine there were 5, I'd guess she could be due soon.....as in soon or maybe a few more days. Maybe the discharge is her mucous plug??
Temp drops can be a bit lower for whelping time & steady (low) for 24 hours, but different strokes for different dogs. Loss of appetite is another possible sign.