This is a really simple framework I think that could use some more spice to it. From a technical side I would definitely allow users to use WASD in addition to arrow keys. The game is a little easy to cheese, jump in and spam spacebar. Maybe having more ways to interact like the enemy crouching or blocking to mix up the player. On top of that just adding more juice with health bar flashes or screen flashes if the player gets hit. I liked the SFX and the bits of story interspersed in.
Good job!