Fine game, but the difficulty feels odd. The bullet patterns are mostly just the enemies shooting straight forward which isn't very interesting to dodge (and it's pretty unintuitive when you're directly below them to shoot). It gets old quickly due to lack of hazard variety. There should be some more difficult hazards appearing as you progress to make it less of an endurance test. I feel like the arrows warning you appear too early, making you already move to a safe spot when really you've got a lot of time still.
As for the polishing, there's no feedback when you take damage. Setting the volume is tedious. You could add screen shake when the enemies explode. Also an indicator when you hit an enemy (usually it's flashing white).
The game looks fairly pretty, maybe consider adding another parallax layer, a bit of glow and particle effects to make it pop.

Pretty solid for a game mage in a month! The graphics are great and it's easy to play! My only suggestion is a feature to make it fullscreen.