Un/familiar noises that scare you

 I was thinking about the bumps and cracks and dropping noises that you hear sometimes late at night.  It's all the more pronounced when you are alone or are the only one awake.  And it's a convention that's often used in horror movies -- especially from the point of view of children or young adults.  Part of how horror movies often increase the "tension meter" in the movie is to use these noises to suggest something sinister, something that is the CAUSE of the strange, unexplained noises.  In real life (whatever that means), it's mostly really boring reasons why the noises happen -- the house is settling, an object like a cell phone (um...) was left on the edge of a table/chair, the cycling of a heating/cooling system, the random noises that normally aren't paid attention to like rain or wind.   But what's unsettling is that I've often heard in Flagstaff a double-sound like a foot step in the hallway.  I never figured out exactly what causes/caused it but investigating the noise(s) often makes the situation worse.  And one can really start to scare oneself if begins to start worrying/catasrophizing (sp?)/horror projecting (???) when one is alone or even when one isn't alone.  That's when the narratives of so many awful news stories and horror movies and urban legends begin to spin out little possible narratives that can't completely be dispelled.  I hate that I understand a little about probability because a .1% does actually turn into a real situation once in a great while.   It should be comforting that's there's only a tiny fractional chance that a noise is actually a sign of something horrible (I just looked over my shoulder as I wrote this sentence), but I kind of do the glass half-empty thinking.   My past as a diving instructor and cave explorer comes into play in an unhealthy way.