How much weight do I have to lose?

Hi, Im 14 Years old and im 5"2, I am about 143 pounds and I'm trying to lose some weight, I do have more muscle than some of my friends and that Might be why im heavier than most of em, but I still have a stomach that stick out a little, Im doing the hCG diet and im doing pretty good (I lost 7 pounds so far) and Im trying to get to about 115-120 pounds, I was just wondering how much weight do i have to lose for my stomach to be flat and not jiggle?