Hi @nainaztengra,
Well there are many superstitious beliefs exist in every religion of the world. For example;
If black cat crosses your path then something bad is going to be happen with you
If crows chirp on the roof of your house then guests are coming to you.
If you awake late night and go to near the fire place it will destroy your fate.
If you throw garbage back side of your home then you are inviting ghosts etc etc.
So my take on this is: Yes you are right in this particular scenario of sleeping in any specific direction.
Let me share the ISLAMIC Theory with you according to which :
One should sleep on side by putting one's right hand under his head. It controls your blood vessels and blood pressure. This position gives you an overall ease while sleeping.
As you mentioned ;
We know of the magnetic fields on the planet, the North Pole and the South pole. When you sleep your pulse rate drops then the normal what it would be when you are engaged in your daily routine. The body automatically makes these adjustments.
If you are in the Northern hemisphere and if you sleep with your head in North direction, there will be a magnetic pull which will cause a pressure on the brain. Iron is one of the important ingredient in our blood and when it comes in contact with the magnetic forces it gets pulled towards it. Magnetic forces are strong and if your blood vessels are weak they will create a direct impact on your brain with the high pressure built up with the continuous placement of head in the north direction. If your systems are strong enough still you will have an impact, because of the pressure on your brain, you will get up with agitation and irritation cause of the excess circulation. A daily dose of this keeps adding up and eventually you see things getting messed up in life due to your own behavior and capacity issues.
Now the same applies for those in the Southern hemisphere, they should not sleep with their heads in South direction because it will bring the same impact.
Also this is not the sole reason, there can be multiple reasons for ill health and disturbances but this can be one of it.
They way you put awareness among the mass is appreciable and i do believe your logic is very much authentic of sleeping position and direction.
Keep writing such great blogs and stay blessed @nainaztengra :)