This game was honestly pretty fun. It's a great concept, just needs a little work on the execution. A few things I would suggest:
-more variety in music
I like the song you picked and I think it fits the game nicely, but when it's the only thing you hear in the entire game, it can wear on you.
-sound effect for charging
When I was charging, there were a few times when I was paying attention to patterns, got ready and lined up my shot, and then fired.. but nothing happened because I wasn't charging. Sometimes when you click it doesn't start and so you have to start drawing again. This is easily remedied by adding a sound effect when you're charging. Either that, or..
-graphical bar for charging
Instead of using a percentage, using a charge bar would be a little more noticeable.
-restart button
There were a few times where I wasted my arrows and couldn't win the round with what I had left. But each time I had to fire all of mine off so I could die and restart. A restart button would amend this.
-faster charge
One thing that would've really helped is a faster charge speed, maybe one that goes backward to 0% after you hit 100%
This is actually a pretty decent game, gameplay wise! Keep at it.
Also, monkey nipples.