This is kind of embarrassing but...?

when you are nearing your period your body can hold onto fluid and your breast get larger and more sensitive , sometimes even really sore.This is all due to fluctiating hormones and once your period is finished for that month you will notice relief...you feel lighter, your breast are back to normal and you get less cravings for junk foods , carbs and sugar. I suggest you get a bra one size bigger to wear at this time of the month so the girls have room to expand and feel comfortable not all squished up. I know all this because I have experienced it many times.

Im 27 and I get it now.. I put it down to a period pain. I've been getting it for years and I can tell you now.. My boobs havent grown any bigger.. I they were growing they'd be massive and I'd be one happy girl lol.

Yes most women's breast grow until age of 21