Question about moving to Japan?

Question:

Hi,
I'm a second generation Japanese-American(nisei) and I will be moving to live with my grandparents in Okinawa. I will be attending an international high school that teaches in English and i was just curious about a couple of things. Will I be treated like a foreigner because I was born and raised in America or will people consider me as a regular citizen because I look like one? What do the native japanese people think of second generation japanese?

Another thing is that I speak proficient Japanese because that's all I speak in my house to my parents who only know Japanese, but I only have the vocabulary of about a 6th grader in japan(I'm an eight grader) so i was wondering if living there would increase my vocabulary pool. and I lack in areas such as using keigo(dunno what the english translation for that), so i was wondering if i would become better at that too.

I also wanted to know if i would start to speak in the local dialect of okinawa after living there for four years. (I speak in the standard dialect which is kyoutsugo/hyojungo)

Thanks(: and sorry for the long question

Answer:

Seems you're going to an international high school. Then people there should be different from average Japanese citizens, or even more Americans (because US military base occupies 18% of Okinawa) You might find school mates who have similar background to you, with different 'dialect or accent' or different level of Japanese language. And as far as you live with your grandparents, your Japanese will be more natural including keigo problem.
Don't worry and enjoy your school life.