Need Help ASAP Please Read Puppy Involved!!!?

Ok so on Tuesday,June 28, 2011 one day after adopting my German Shepherd Dog puppy she somehow got her stitches wet from her spaying, and they were the dissolving kind. Well her guts and all that came out. No lie! Everything came out!! We rushed her to the vet, and they fixed her up, and she's been using the bathroom without struggling. Her poop and pee color is normal. But my puppy Riley can't hold down her food. She eats it then throws it up. There is NO blood in the vomit. It's just her food and mucus. She can hold down water though. I am very worried about my newly adopted little girl. We're calling the vet tomorrow, but I was wondering what can cause her to only vomit her food and mucus!? Any suggestions so I can ask my vet!? I am literally about to cry because I have only had her for almost two days, and she's so special to me!! Like said we're calling our vet first thing tomorrow morning!!