Hi! We had a similar problem with our little bundle of joy. Happened after a weekend boarding trip. When we picked her up she was fine, excited to see us, etc. We actually have two girls and only one ended up acting similar to yours after the weekend of being boarded. Roxie was very lethargic, wouldn't eat, would only attempt to drink and when she did, she would throw it up. She only wanted to sleep - which is VERY unlike a puppy! I took both pups in because I was concerned it was something like kennel cough and that they would both end up with it. As it turns out Roxie had gastroenteritis. We had to give her antibiotics, special food (Science Diet i/d) and limit how much she ate for a couple of days. We now feed both of them the dry Science Diet i/d and after we return from a trip where they have been boarded we make sure they don't gorge themselves which is what brought on the gastroenteritis. May not entirely be the same situation as yours, but maybe it will help. Good luck!
