Great work, for your first game! This is the kind of stuff that makes me glad I came back to NG. Keep up the good work; you can only get better from here.
If I know anything about actionscript I would like to look at the source when it's released.. I might learn something, haha. It reminds me of some game or minigame, I don't remember what.. Hmm.. Overall, great work, a 5/5, and 9/10 from me. As aforementioned, perhaps try to add some more things to get in your way, powerups, or something. it can add some spice to a game, and even make the simplest of games a touch better, not to say you are off to a roaring start already!