Thank you for this long and interesting comment.
At the beginning I wanted to create a more action oriented game with some enemies, but due to the lack of time I didn't put it except for the laser. However, with no health bar it's true that the lasers don't do much.
For the part with the button behind the glass, you have to shoot a shield and then shoot with the red weapon on your shield. The red bullet will bounce on the shield and go right to the interruptor.
Thank you again for all the feedbacks!