Okay so um, this is kind of a personal question but um....

I think you are far too young to be worrying about the size if your breats or butt i'm 15 and none of my friends or i worry about the size of our breasts when I was 13 I was "flat" but as you grow so do your body parts.

You are in the very early stages of puberty and I would be surpriswd if you have only now started to get your period.

Dont you worry about that for now wait until you're in your mid to late teens, all you can do now is eat properly and try to,get as much rest as you can as all this contributes to growing and development of a healthy body.

Enjoy your young teen years and dont worry avout what they say you'll grow into a woman soon enough