How many times have you touched your dog's nose and it is dry? I know when I have felt my dog's nose and felt that it is dry and warm, to me, it was like I was taking my dog's temperature and the indication was that she wasn't feeling well. I usually did this after she appeared sluggish or not like her usual playful self.
By all reports, this is an accurate indication that your dog is not feeling well. Our dogs should have moist, smooth-surfaced noses with a consistent temperature to the pads of their feet. Dogs that are ill aren't able to keep themselves hydrated. They also most likely aren't eating normally which will add to their dehydration.
Keep an eye on your dog and watch her behavior. If she stops eating or drinking water, check her nose to see if it is dry, and then contact your veterinarian for proper care.