I had a kitten once, well he was around 6/7 months and I found him meowing outside, he was very withdrawn and limping like your girl.

We took him to the Vet and he had broken his hip. I have no idea how he done it but it was a nightmare. He had to have an operation and then he was secluded in a small area of the house so he wouldn't walk around much.

He was fine in the end but is nature changed dramatically. Which made me wonder if someone hard hurt him deliberately.

Yes, you must go to the vet. She will be in agony if she has.