I'm at a healthy weight, but i'm not healthy. Please help me?

I'm 15, weigh around 127 and am 5'4 to 5'5. Technically, i'm at a healthy weight, but my thighs jiggle and i have about 10 pounds of belly fat, not to mention a muffin top. I was just wondering any specific things i could do to drop around 15 pounds to look healthy and feel great!! What do you guys do to stay in shape? Also, it's really hard for me to not over eat, any pointers? Thanks guys! I'm a girl by the way.