Nice gameplay mechanics, its certainly fun. I agree with it being to sensitive although you do get used to the controls after a while. The level of challenge is decent and I wanted to continue on after each level.
Not a fan of the artstyle, this better presentation and polish, this game would have been far more enjoyable. I believe you could have presented the enemy/shooting blocks better and to have the player stop until he was killed was frustrating, I understand you needed to kill the player in the line of sight but I think it should have been done by instantly killing the player rather than waiting a bit for a bullet to hit him. Like it could have been an insta-kill laser or something.
Apart from that, great work! I would certainly advise you put more polish graphically into your next game though.