Hi,
I played your game and enjoy it. It's fun and weel made. Pico8 is awesome ! congratulation.
To help you improve your game i have 2 little things to say. Maybe you can had music ? And also, some ennemies a shooting at the player, but when this enemy is on the left or right, this is impossible to avoid for the player (almost happen to me once).
So yes, I enjoyed it :)