Here's a revised version of your critique:
"It's a funny little mini-game. I like the art style for the first level.
Critique:
Level 1 - I was a bit confused because there was no direction on what to do. Knowing the objective of grabbing the gun would be helpful.
Levels 2 & 3 - I noticed that when enemies get near the player, it's challenging to shoot them; you have to create some distance to hit them. Regarding the gun, knowing where the bullets shoot would be very helpful, and increasing the bullet speed would be great. It's really difficult when the bullets are very slow, and the crosshair disappears."