Pretty Good.
As your first movie though, It had flaws.
Your biggest flaw was definitely having some choppy animation at some points. Also, I think putting some color, would have been good. Even if it was simply adding an extra shade of black or something on occasion. I know its a doodle though.
Also some parts looked downright silly. Such as when the arms were flailing when the kids were running down the road away from the flies. That part could have been touched up quite a bit too. It wasn't bad, But the arms were noticeable.
Lastly, The small of problems, Was the music. I found that it really didn't fit the song much at all, And if you browsed the Audio Portal for a while you would have had much better music, To go with your animations entire style.
Solid effort though.