My biggest complaint would be, that enemies spawn on me and I die from that, which is super unforgiving. You could make the player invincible for a short time when the spawning happens or mark the position for a few seconds where enemies will spawn.
Also I would have preferred the Space key as the attack button, because my thumb is free, but pressing E requires me of letting go D.
I really like, that there is an indication for the current attack power (and not only for the HP).
Great job on finishing your game :)