A unique take on the theme which I really liked, having to navigate your ship whilst also aiming at the same time - it gets quite tricky as the game progresses!
I would have liked to see more power-ups, maybe something that upgrades or changes your engine trajectory, or a shield or something to add some variety.
But overall a fun little game. I liked that you added damage indicators for both the player and enemies, and very cool that you wrote it all in C too!