Does anyone know the name of the creepypasta, where it starts with a man waking up from a dream where he could remember nothing but a bang or nothing at all, and going into his workplace and killing everyone (I'm not sure about this) but it ends with him killing himself and he wakes up with the ending written exactly like the beginning?
I recall that the guy was talking about a thing he bought, which was a gun.
Picture unrelated.
Found it. It was "Just a "nightmare""