Thank you very much, we too are very proud of our art and what we could create in about 30 hours!
You actually have kind of a choiche which weapon you use. With RB/R1 or Space on the keyboard you are able to switch manually through, although they will shoot when they're cooldown is up. The cooldown even stops in the middle when you switch.
A lot of players didn't knew that so that's entirely our fault for not communicating the controls well enough. At the moment we're polishing the game and we put a litte control sheet on it!