Would be nice if it was faster and/or had an upbeat 8bit music. Shooting 2 missiles at once is nice, but the distance between them makes it quite hard to use both of them to hit an enemy and the green ones need that (they seem to be quite stronger than the others). Lastly, after a while it gets a little bit repetitive. But given that this is your first game (I am a beginner, too) and you managed to complete that in 2 days only (my game does not even have a start menu), it's quite impressive. Well done, good job!