Very good game, I enjoyed it a lot :)
The art is awesome! and the SFX of collecting items is very satisfying :D
At level 3 I just sent heads up up and away, but then, alas, i fell all the way to the bottom lol
"Boys can't cry" made me lol hard
the shop menu is blinking each time you open it, made it feel laggy (i think its a feature though and not a real lag)
The head mechanic could use a tune up, I was just trying random things until I figured out how it worked
When hitting an enemy with your shot, you can add an indication they were hit.. The bullet didnt get destroyed and I thought it just didnt hit the enemies (even though it did)
Overall - Very solid game :)