Needs a LOT of work.
The animation was crap, for one; learn what a tween is, a motion tween in particular. Also, there was pretty much NO plot at all. Thirdly, the voice (or that's what I THINK it was) was annoying. (I don't support voices in Metroid animations, due to the fact that nobody knows what the characters voices ARE.)
All in all, come back once you've learnt a bit more about flash. And hopefully the Metroid series as well.