Great concept
Good graphics, nice idea, good game overall.
Here's some bugs I found:
1) The final screen has 'safely' spelt 'safly'
2) The final screen 'press space to restart' doesn't work
3) The score does not show up until the final screen - it says NaN
4) The option to gain energy while fighting disappears if you restart and/or reach level 9 or something like that.
Some suggestions:
1) Add more types of heal - a massive heal that takes ages to use perhaps, or a heal over time.
2) Add more types of enemy/paint blob/thing
3) Add status effects - perhaps a poison that damages over time and can onl be healed by a certain special heal. Or perhaps a debuff that stops your energy charging until it is healed.
Good concept though...keep it up!