size of breast is determined by your heredity and hormonal status. usually tall thin girls have small size breasts. actually, reason behind their tall stature is their low responsiveness to sex hormone. usually breast size improves slightly after marriage and childbirth but not up to mark. in such cases breast augmentation through plastic surgery is the only option. its very safe and simple surgery.

I am 13, "5,3" and i wear a B cup, my friend wears a D cup, i feel like I have really small boobs, do I? :/

at the age of 13 you should focus on your study and not on size of breast. at this age rapid growth makes you tall and thin, after you acquire full maturity your body will start hetting volume. anyway your height is very good. have good helathy diet , light exercise and focus on study and carrer. dont compare with any ione else , every person is singular.

i have tried many many many pills creams and meditaion route. they have all been a wast of money... please dont waste yours too.  its an internal status.     cranial sacral therapy can adjust your pituitary and other hormone creating parts.   .... there are some herbs that i have seena  small difference with, but none permanent.....i do not suggest implants at all. the life span in max 10 years and have been linked to tumors and other issues. ......I am learning that my a cups do not make me less of a woman and my man loves my perks.....what helps me feel better is building my booty muscles and watching the full breasted ladies check my rear out repeatidly.    just focus on what you have thats what works best for me and the older your get the less you care about those man bags.  we  are lucky to be pettities