What Do You Do When Your Puppy Has A Stuffy Nose And Cant Eat?

-.- Don't put a dog down because it has a cold. That was a PATHETIC answer.  Massage the top of the dog's nose and the puffy parts of her muzzle. Make a vet appointment if you dog has a stuffy nose for more than 24 hours. Get a cool mist vaporizer and run it near where your dog sleeps. This
helps to keep her bronchial tubes moist and makes it easier for her to
breathe. Turn the hot water on in the shower and close the bathroom door. Do not turn the
exhaust fan on, so the bathroom quickly fills with warm moist steam.
Sit in the bathroom for several minutes holding your dog to help clear
his nasal passages.. Hope this helped.

You need to take your puppy to the vet, but 'till then, try giving him/her egg (not cooked or beaten). Try hand-feeding him/her too, by opening their mouth with your fingers and putting a tiny bit of wet dog food on the end of they're tongue. (If they don't consume in around 15 seconds, take it out of their mouth so they don't choke).

You need to see your vet. You almost surely need antibiotics. It may be moving into the lungs causing life threatening pneumonia considering the severity your describing. Also many other secondary problems including hypoglycemia from not eating. Do not try to force your pup to eat or you can force particles into the lungs and aspirate them. Have your vet tell you what you need and what you need to do. They carry a food called A/D that usually is great when they aren't wanting to eat.