We have an 8 month old American Staffordshire Terrier puppy that we've had since she was 8 weeks old. The past few days, she's been very lethargic. She won't eat, drink, or move and her back legs are stiff. She normally downs her food in a couple of minutes, but now she won't touch it. We took her to the vet today, they took a whole bunch of tests, which as came up negative, did xrays, and put water in her back because she was dehydrated, they didn't find anything wrong with her, so we spent $400 to find out nothing is wrong with our dog She has all her shots, and was perfectly healthy and happy up until a couple days ago. She eats everything and anything, so we thought she might have gotten something clogged in her stomach, but the vet said the xrays would have showed it. Anybody have any ideas what's going on with her?