Well done on making and submitting something!
The movement controls took a little bit to get used to, but it started to click after trying it out for a few rounds. It also took me a minute to realize that the guns were working, there just wasn't any projectiles. They did still seem to glitch out after taking out a few zombies though. I also noticed there's no obvious way to get back to the main menu if you look at the instructions/when you die! I just had to exit the page and load it back up.
But those are all things you can add next time! Major point is you made and released something! Great job!