This was a cool experience, you really achieved your goal of setting a worrisome atmosphere and nailed the theme at the same time. It's so satisfying to solve the morse puzzle but also a bit creepy as all the convos are about bombs, ammos, etc.
Making the fps control scheme a little bit less sensitive would improve the experience a lot, sometimes, that's the only thing I found annoying. Also, I didn't understood you could type in the paper at first, but your help page explained it well. Maybe a suggestion would be to have that instructions handed over on a paper under the door? That would make for an immersive tutorial :)
Oh yeah, and the gameover jump scare hits quite hard the first time!
Thanks for making this game!