first of all how tall are you. Coz 90lbs is very small and if you are anything over like 5 4 even, then thats like underweight!
Even if you are short, about 100-117 is a good weight range for you to be in. You really DON T need to lose any weight. If you want to tone up however, try some weight lifting/strength training. That can give you a cute athletic physique.
