Three nights in a row is not nothing. That's a pattern and patterns matter more than people give credit for.
I had something similar back in the late 90s, stood in the corner of my bedroom rather than the foot of the bed, but same sort of deal - completely still, no features, just this solid darkness that was somehow darker than the room around it. Went on for about a week then stopped as suddenly as it started. Never got a satisfactory explanation for it.
The thing I'd want to know is whether it felt threatening or just sort of... present. In my experience that distinction matters quite a bit when it comes to working out what you might be dealing with. Some people report these figures as almost neutral, others say the dread is overwhelming.
Did you try talking to it or acknowledging it in any way? Curious whether that changed anything. A few accounts I've read suggest that direct acknowledgement either escalates things or makes them stop altogether. Would be good to hear what others make of this one.
