I would consider make a bigger screen, I guess it's ok to scale the game window as long as original resolution is respected in the game.
About the game itself it is pretty fun and enjoyable, but also pretty hard. I'd add a lifebar or checkpoints to not have to restart the whole level each time you get hit. I would also change control scheme, ctrl key is not a good action key.
Maybe I'm getting a little grumpy, I enjoyed the game ans there's a lot of good work on it. Nice entry overall.