Am I healthy?

Yes you are at a great weight being that your 12 5'5" and 115 - 120. When I was your age which was a long time ago I weighed about the same and thought I was fat we didn't have the internet back then to do weight height. But I would say your fine just remember eat well eat lots of greens and continue being athletic it will help you as you grow and you don't quit growing until you are 25. So be good to yourself your great in all of our eyes.
Crystal