hi, thanks for using healthcare magic
It sounds like the girls at your school are bullies and are the ones with the problem.
At 5 ft 1 inch and 84 pounds, your weight is not in the overweight
category and you do not need to lose any weight.If you do lose weight, you may fall into the under weight category.
If you find that you are overly concerned about your weight or body image, it may be best to speak to your parents or guardian or any other adult you are close to.
Hope this helps