I agree that she was taken from her mother too young and didn't have a chance to learn her socialization skills. Having said that, I have to say that Kalina was a bit like that too and I got her at 12 weeks. She outgrew it though. She's almost six months now and she doesn't bite at all now. She still growls, but it's playful growling and you could kiss her on the mouth at the same time she's growling and she will kiss you back. I do think terriers are inclined to be growly - it's their way of talking. We just had a "good growling" thread recently.
I would definately have her seen by a trainer, but she is still very, very young and it could be something that is not very serious at all.
