How can i get rid of my belly bulge?

okay, I am twelve years old 5 feet tall and weigh 99 pounds, is that normal? I have done almost everything I can to get rid of the belly bulge, I dropped soda, and I don't eat that many sweets and I have tried crunches, jumping jacks, jumping rope, squats, walking, and maybe a little weight lifting but nothing is helping me get rid of it not a thing! If some would help I would be so happy because i am so self conscious that when my mom asked me if I wanted to go shopping for a bathing suit I told I wasn't ready! and I love bathing suits! please help!