Have you ever been scared by your own mod?

[Vale]

I was testing one of my maps, and at one point I had edited the script and retested it so it wouldn't play the music to go with the level. While testing, I found that in one of the rooms there was a thumping that sounded like footsteps or something.
I assumed it was something colliding with another object somewhere, so I spent a while looking for it.
I was unable to find the source of the noise, which would start and stop at random.
It creeped me a fair little.
As for actually being scared, on my old computer I was developing a couple different mods, one which was an amnesia minigames bundle (essentially custom stories not runnable from the main game but only from a special full conversion.) One of the minigames took place in a dark maze where the player had to survive three minutes, and as time passed the game spawned more and more brutes into the dark space to wander around looking for the player. I was somehow so scared the entire time that I used an exploit that I knew of to hide through the whole thing just to make sure the victory system worked.
Unfortunately, my cat broke my last external hard drive that I had the project on, so it was lost.