hi crazyhound! Thanks for stopping by to play :D and yes you are correct the basic flow of the game is a day/night cycle.
Nighttime- shoot those ugly vampires and defend your saloon! You can shoot through the windows and doors so you can pick those suckers off before they start tearing down your doors and windows. However, should the little stinkers do damage to your windows or doors, you can repair the damage by walking over to the hammer icon and holding “e” to board them up.
the first day phase happens when the score hits 60, but you only have 20 seconds of respite before the next night begins. Hope that helps you gauge how far you need to make it to 😃