If she was my dog, I would not wait for 3 weeks! I would take her in, the sooner the better! If she, her mother and her siblings,were found behind a dumpster, God only knows, what kind of environment they were all in before that, and what they were all exposed to, there is no telling what kind of problems she has. Her symptoms are not normal! I used to breed Chihuahuas and all of mine at that age, did sleep a lot, because that's what babies normally do, but they were all still always very active, eating, drinking, and playing, when they were awake. Chihuahuas get dehydrated very easily and if you are not careful, and they don't get re-hydrated fast, they can die. I noticed that you said that you bought a kennel and a dog house. I really hope, that you are not planning on leaving this puppy outside, because Chihuahuas are Indoor dogs. Chihuahuas, should Never be kept outside alone, because there are too many sky predators, like Eagles, Hawks, Falcons, and Owls, that can see them as prey, and have absolutely no problem at all, swooping down, picking up a Chihuahua, and taking off with it. It has happened! A Chihuahua, when outside, should always be supervised and you should always be aware of what may be stalking them nearby. When it's cold outside, Chihuahuas get cold very easily and if left outside in cold weather, can freeze to death. It doesn't matter what kind of shelter they have! They have no body fat on their little bodies and cannot maintain heat as well as other breeds can. When it gets really hot outside, they can suffer Heat Exhaustion and die. I feel that all dogs should be indoor dogs! They are pack animals, part of the family and belong inside with the family. If you cannot keep this Chihuahua inside with you, then please consider surrendering her over to the vet. They will treat her and adopt her out, to a good loving home, that has no problem with her staying inside! I hope this little one makes it! I would also tell your grandma, that if she has any of the other puppies and the mom, they really all need to be seen by a vet. There is no telling what these poor dogs were exposed to, before your grandma found them, and if any of them are going to survive, the only way to make sure they get every chance available to them, in order to survive, they all really need to be checked, as soon as you can possibly get them in to the vet. The sooner, the better!!!
Former Chihuahua Breeder Of Several, Now Spayed And Neutered Munchkins!
Have owned Chihuahuas, for over 40 years!