Here's why it's okay and some things to keep in mind:
* Puberty Varies: Puberty happens at different times for everyone. Some girls start developing breasts earlier, while others start later. There's no "right" age to have a certain bra size.
* Genetics Play a Role: Your genes influence your breast size. You might be similar to your mother, grandmother, or other female relatives in terms of breast development.
* Bra Size Doesn't Equal Maturity: Bra size is just a measurement. It doesn't reflect anything about your maturity, personality, or worth.
* Comfort is Key: If you're comfortable without a bra, you don't need to wear one. Some girls prefer to wear a bra for support or modesty, even if they have a small bust. It's a personal choice.
* Finding the Right Fit: Wearing the correct bra size is important for comfort and support. A 28AA means you have a small band size and a very small cup size. It's possible that some of your friends are wearing bras that don't fit them properly, which can make their breasts appear larger than they actually are.
If you're concerned about your development or have any questions, talking to a trusted adult, like your mother, a female relative, school nurse, or doctor, can be helpful. They can provide reassurance and answer any questions you might have.