we got her for my daughter 3 days ago and she lays around most of the time. she is 5 months old. She has puked 3 times ( after car ride). Her poop is black and tarryand runny,with a little blood around anus.. Dog is up to date on shots according to previous owner. Is this normal? I havent even heard her bark yet.. She is a very sweet Rat Terrier, and she has already learned to use a leash.

Dont trust the former owner on this one, go to the vet as soon as possible. Just hope that it isnt parvo.

I would take her to the vet immediately. Sounds very serious to me, especially your description of her stools. Puppies get dehydrated very easily, and can die within 24 hours. At the vet's they can give fluid treatment apart from anything else.

Puking and runny with blood is an emergency.

your previous owner was lying to con u into buying the dog. a healthy dog would not be like this
take it to the vet immediately

do u have a copy of its vaccination or medical record? for u to be assured that the dog is really up to date. based from the signs u said, the dog is sick. and hopefully it wouldnt be that deadly viral disease called parvo virus which usually attacks young puppies. you better see ur vet to make sure...