Flash file saize problem

I am a new in flash. I learn some basics in FLASH MX 2004 and made a home page.
The problem is that it is too big. Well the thing is that when I save empty flash file it size =32kb. then drow a circle and save size rise to 42kb. Then I delete a circle and remove it from library the size stays the same why is that?
I think it`s the main problem for me ?

Thank you