The equations you find online are estimates that get the average person in the ballpark for gaining. They are not absolute, set-in-stone universal requirements. While they can give you an idea of how much to eat, ultimately you will need to tailor it to your own physiology through trial and error.
To determine how much you need to eat to gain... start eating until you start gaining weight. Increase the calories until you are dissatisfied with the rate of return (i.e., you start putting on more fat than you are comfortable with), then scale back to where you are making progress you can live with.
However, eating to gain is, for many, a difficult thing to do when first starting out. Stomach aches can be common while your body adjusts to the added bulk. To make optimal progress, base your needs off of the results you see in the gym and on your body, not necessarily how comfortable you are with the process or what a math equation says is SUPPOSED to work best for you. Oftentimes, one might need to "eat through the pain" to get where he needs to go, but it isn't a requirement for success. Lifting shouldn't always be an AnimalPak ad... suffering for the sole sake of suffering might make you feel hardcore, but it ultimately isn't going to put any more muscle on your frame.
If you find need to eat more, eat more. If you don't need to eat as much, good for you... save a couple of bucks at the grocery store.
And, yes. You ARE weird. A fuckin' god damn, bonafide, Grade A, bearded-lady-juggling-on-a-unicycle, high-octane octo-mom freak show.
But that has nothing to do with your caloric needs... just a general observation.