Hello thank you very much for sharing your karma.
About the firing of projectiles, there are several culprits. The first is me, who designed a 15×15 character with a 13×13 collision, and the other is the engine, which by default does not support wall collision in projectiles. For these reasons I ended up not realizing it, so I put more open areas.
The shot is defined by default directed upwards, you change this when shooting while moving, with a new movement a new pattern is set in the direction, so if you shoot again, and you are stopped, you will always have the last shot direction.
Another strange mechanic is with the "z" button because combined with the "x" you shoot defining the direction without moving.
This strategy of shooting at a wall and then shooting was the first thing I put into the game, I'm glad you highlighted it, it's confusing, but the game wouldn't be a puzzle but a shooter.