Perplexing 8 yr old - deep rooted self hate?

Daughter is very complex child. Outwardly she is social, smart and very pretty with lots of good life skills. She suffers from Sensory integration disorder and has exhibited extreme fear over certain senory issues (fire drill, vibrations, dentists) She has an extreme fear of being by herself. She has also had an obsessive personality - first with airplanes at age 3, then cars, then antlered animals now dogs.  She has expressed an extreme dislike of herself, saying things like she has a weird face and she wish she were different.(sometimes wishes she were a boy sometimes a dog etc...) At age three she would sometimes refuse to look in the mirror saying "she didn't want to see the self" She is tomboy and insists on wearing only boys clothes and wears her hair in a pony tail exclusively. I really do not know what to make of her and want to help her now but am not sure how. Lately she is having recurring concern about her adult teeth falling out. She can ask me 5 or 6 times a day if her teeth are loose. Sometimes I feel she has OCD and sometimes I am concerned that she really wants to be a boy. For her 8th birthday recently she told me she wished she were a cool boy.

She is adopted and I have no idea of bio parents mental health. Suggestions?