I'm not sure how much I should weigh?

I thought I should be about 105-107 but right now I am 106 and I am still a bit heavier then I should be. I am 5'3, 14 years old, and 106 pounds (as stated above). I know it sounds perfectly healthy but I still have a lot of "chub" hanging off my calves and arms and its not that pretty if you knows what I means. So I am going to keep running and hopefully lose that- but about how much should my goal weight be?