Not bad.
Well I heard you are trying to be a better animator so here are some tips, and I'm not exactly a professional either but I do a lot of flash and seen pretty much every Flash on this site since 2000 so I have a pretty good idea what looks good or not. Anyways, try not use the 'Linear" type of colouring when filling in stuff, it just doesn't look professional and looks like you are trying to cut corners and time.
Just shade it a bit, might take a bit longer but you will be greatly rewarded. Also, try not to use thick lines, it simply doesn't look good. Try to hand draw some more and less motion tween and if it's too hard, use it only then or when trying to move things that don't really have much movement like backgrounds or zooming in (The idea is to try not make it too obvious you used it).
When you have draw things your not too great at, you might want to zoom in a bit more and show what you are good at. Hmm, I will stop at that, and I wasn't trying to insult you or anything, just feedback and tips! the animation it self wasn't bad (along with the music) but you might want to work a bit more on it. Good work and keep it up!