I'm not sure how I got this to happen, I think i was spamming buttons in the end screen and then when I quick restarded I quick restarded again while in the "press space to start" screen and then it happened. I restarted my game multiple times but that didn't fix it.
I found out what causes it. if you die after finishing a level (by placing a block, as shown in the video) you get sent back to the start menu. you can then press quick restart to get a 0 second time. (in the video i started first before quick restarting to showcase it)
I experienced a weird bug where my time on level one shows up as 0 seconds. thankfully it isn't on the leaderboard though.