When you use lots of images/sounds/video in flash your final file size can be huge!!
What you can do is lower the quality of your images/sounds which can make a big difference on file size...Don't worry you will hardly see the difference too, you wont loose much quality :)

Go to publish settings (File > Publish Settings or Ctrl+shift+f12)
you get this menu here you have many different format you would like to publish you flash with...go to the flash tab

Go down to .jpg quality here you can assign the quality of your images I mostly use it at 90 which can save you a lot of file size at the end.

If you have audio in your files you can set their quality too, click on set for each one and set the bit rate on 32 kbps quality best for both.

Thats it try this with your files and see how much you can save from you file size at the end...its worth it! Many designers forget those important settings.

*remember you can set it as much as you like or prefer, try different settings to see what works best for you keeping in mind quality versus file size.