The Overflowing Bra

That was really lame. Here is the TL;DR:
"Queen has a magic pendant, breasts grow as big as rooms in the space of a sentence or two. Guy comes, kills army, breasts shrink to normal. Queen kills guy, breasts grow even bigger than the room in yet again 2 sentences"

Kinda feels like a quick brainstorm sketch that spins out of control after the author gives away the farm.  

I must echo the other comments already made by others. It is a little too short, but I think it can be made longer by putting in more detailed descriptions of the BE. More background story/plot would also help greatly.
You write that they grow with more power but you could put in much, much, much more details. For example, how the growth starts, what does she feel (what sensations) when it happens, what is she wearing, how did she gain this ability.

Interesting idea, but please don't resubmit until you can hit the four page mark.

Theme song for this story should be "Don't Stop Me Now" from Queen, as the last sentence is read.
Cute story. :D

For your first story in English, it's passable.  However I would strongly suggest writing your story in your native language and then finding someone to translate it for an English audience.  With this, you'll be able to add details and depth that will greatly increase the presentation of this good story seed.