Hmmm - Good first try
Animation - Scratchy, but seeing as it was your first submission it was decent. Just add more detail!
Story - Not much of a story here. Shoot invading .... things in a INVADER fashion. Just keep trying.
Sound - Good rock song, I personally enjoyed it, but what if the player is not a fan of rock?
Overall - Good, you should try involving breaks in between the levels and make sure it only shoots from where the enemies are. Good first try!
-GS-
-Mu-