Advisezzz...
Here:
First of all I noticed the low framerate. Speed it up and it'll look MUCH more professional.
Second: The plot was unclear...
Third. Use sound effects. It was only the music playing, and it can be boring to watch.
Fourth: Add easing to the tweens.
Fifth: More frame by frame...
I liked your detailed drawings. You said that you had been working with Animation 4? What's that?
Keep it up, and MORE FBF (frame by frame :D)
Good to be your first flash!