I was between 110 -115 pounds.
I can relate to this, save for my bones were not as visible. At your age, I was about 100-110 pounds at 5'8. I was tall but...wouldn't grow taller (I was sure that I would.)
I was self conscious (I had NO figure). I also didn't start my menses until I was 15 years old. I felt like an "odd duck." However, I felt absolutely fine. By the time I was 18 1/2, I did eventually hit 130 pounds.
Outside of appearance, how do you feel? Do you frequently get sick or feel unwell?
No gastro problems i.e tummy issues/bowel (number 2) problems?
If you are fine healthwise-I wouldn't stress over this too much. It sounds like you have a good lifestyle but do hope that the foods you put into your body are good ones.
On an "average" day, what does your diet consist of?
Most "convenient" foods are not good at all. They have plenty of the bad stuff and very little of the good stuff.
~Kate
Would you please state your height so I can better assess your question and help you. Thank you.