I noticed that too, and this was after the game was already published (I was apart of the team who made it). The workaround (jank as heck) is to pause the game and then click Resume. That should set things right. It comes with the added oddity of storing any movement made until the Resume is pressed, so that means you could spam the jump button and then go flying high into the sky.
EDIT: I will say that the rooms are lackluster, but since we are in college at the same time, the development of the rooms was put to the side a bit (whoops). There are also 105 different options for the Zombie's appearance.