confused and slightly worried

Hi everyone, so my name is Emily and I am 14 turning 15 in April and I'm really worried about my boobs. I'm overweight and trying to lose it and I started developing when I was around 9-10. I am currently a 14a (Australian sizing) but I don't usually fill most A cups. I got my period about October ish last year and my boobs have not grown for about 3 years. They are not even slightly formed. They are basically rounded triangles poking out of my chest. They don't hang or droop at all, they are completely attached to my chest. I really hate it because literally everyone at my school has big boobs and I look so stupid because I have excess fat everywhere except my breasts and I'm so confused and worried that I might have a problem or something.