I had fun, but it's simple. If the powerups could interact with each other it would have a lot more staying power. Also, the start is a bit boring since you only have one weapon, the sword, to attack with so you have to constantly back up slowly for a minute+ each restart. It doesn't that the enemies take 3 hits to kill.
Not sure how much you'll work on it since it's a side project, but it has potential. So keep up the good work.