Don't worry, we won't take your qestioning in a wrong way. I completely understand where it's coming from. If you have read all falling asleep sensations thrown together with SP into one bag, it's not easy to reorient to a different idea.
Our body puts us into muscle paralysis called REM (atonia) after we start to dream, so we don't act it out and kick the wall or start punching around and hurt ourselves or someone around us.
After we start to dream. And
paralysis means
not being able to move if your life depended on it. Not hard to move, or close to impossible to move.
Our body is pretty good at hiding this possibly frightening condition (not being able to move) from us and that's why it waits to turn it on after we are asleep and after we start to dream. And it's same efficient in turning it off the second we are awake. I mean, I woke up plenty of times directly from a dream due to some sound or being scared from a nightmare. And I was never paralyzed, so REM (atonia) got turned off on time.
Now, sometimes you may wake up and you realize you trully can't move, no matter what. This condition, when REM (atonia) didn't shut down on time is called SP - sleep paralysis. For some reason your body failed to either notice that you woke up or for some other reason failed to turn REM (atonia) off.
For most of the people this may happen once or twice in a lifetime. For some, it happens more often. Since it's more of an exception than a rule, it's called a disorder. Most of the people don't get it.
I have had it twice, each time when waking up in the morning and this was many years before I even heard of lucid dreaming. It trully has nothing to do with lucid dreaming.
Next time when you feel vibrations, move your hand. You may think it will be hard, because you are extremely relaxed and it's more comfortable to not move than to move. If you start paying attention to sensations, you may notice vibrations just seconds after you return from restroom, or as you falling asleep normally, not even WILDing.
Normally, nothing of this would matter. Because no matter what sensations you do/do not experience when WILDing, you can WILD and enter LD. This becomes important to sort out only because of some tutorials, that tell people "you must reach SP before you can have LD". No, you don't need to be in SP before you can have LD. In fact, you can't induce SP at will. SP it's something our body regulates, we can't turn it on and off when we want to. Then it wouldn't be a disorder. Then normall sleeping would be a disorder.
Now, weather you believe this, or something else, please know, that paying too much attention to sensations of any name can slow down your WILDing attempt. It keeps your focus on your body. When you should be losing track of your body.
Here is an excellent
WILD (sageous) guide. Good luck and happy dreams

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