Im not a girl not yet a women

"Your an adult stop acting like a kid. "

How can I do that my physical features is like 12 yrs old girl. Im so skinny and Im really small in terms of height. I dont even have that things to be called as women. Like the boobs and the ass, that flawless white skin, flat stomach and long hair. And even how hard I try I cant be matured enough in their eyes. Even though all I want is to be independent and understand. And if your thinking that I dont want to be real lady. Your totally wrong. I want and I like to act my age but I guess doing so will just be another issue. Im not a girl, not yet a women. Im the person in between.