Really cool artstyle and gameplay, had a lot of fun!!
I agree with the comments here, maybe you could make him shoot to the direction he's facing.
I'd also make the enemies start moving as soon as they spawn, there's already an animation(which is great!) before they spawn so that the player can prepare. Imo there's no need to make them be idle for that long, makes the game too easy (just an opinion).
Anyway, I loved it. Good job!