Am I Underweight, Average or Overweight?

ok. I'm under 18. People reason I look like i'm 17 but i'm younger later that. I am 5'8" and weigh around 115 pounds. (my Jean size is 0) I am in shape. I am a remarkably active soul. I Bike 3-4 miles a day (with my dog) & horseback ride (but currently i am not riding). And sometimes I will do Hurdles, Jogging, swimming or something similar to that.
I guess I have a small stomach. but I teem up fast and dont guzzle a lot. I drink healthy.
I devise my BMI is 17.5. whacha think? Your just the thing weight would be 140 lbs so you are probably a bit on the street light side and possibly a tiny bit underweight.
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