This definitely sounds like an issue. It appears that your dd is not happy to spend all day doing things that she's known for years. Also, her scores place her in the HG+ category, so chances are she has nothing in common with kids her age, or even a little older. She's physically a five year old with a ten year old mind, and there's now way to have a good match. Is it possible for you try talking to her on the weekend, while eating ice cream or something fun? It may be that she's bored to tears in school, and being with older kids won't help because she could keep up academically, but not physically.
Is homeschooling an option for you? The reason I'm saying that is because I placed my oldest in school and have lived to regret it. He started off a few grade levels ahead in everything, and within a few months in kindergarten he wasn't even reading at home, because his friends could barely read, his teacher said he wasn't supposed to be reading chapter books yet, so he regressed to beginning readers. I have been lucky enough to homeschool my other two, so they're doing much better academically and are much happier than their older brother.
Anyway, it looks like there is more than meets the eye with your dd and it warrants attention before her personality changes completely (my ds11 changed completely, and has stayed that way).
