Interesting, heavy feeling while trying to sleep

[Balthier]

I am a 15 year old male. Just a couple nights ago, I was attempting to go to sleep like normal, right? So I started thinking of things.... And then I imagined myself falling backwards. Spinning backwards, I immediately felt like I was actually being tilted backwards in my bed, and that's when the feeling started. It started kinda in the back of my head and expanded down from there. I was really intrigued by this feeling, so I let it continue without doing anything. After about a minute of it intensifying, it reach kind of a peak. It felt... heavy. Like there was a weight pushing me down, all the while I felt I was falling. Like a roller coaster except there was no movement. I was completely still..and yet... I felt I was being held down, ever muscle from my head, Neck, torso, arms legs, were all being held down... And I realized the lack of sense. It was almost a trance as I was perfectly aware of everything going on, but not a single thought went through my head. I couldn't hear the fan going loud next to me, didn't really feel the blanket draped over me. The most powerful of it was probably in the back of my thighs and chest. This immediately brought attention to my breathing as I couldn't feel it, or my heartbeat through the sensation that has only gone one for a couple minutes. I took a deep breath. I could feel my lungs moving, but they felt almost numb..... I've tried looking into this feeling of heaviness, unable to move, yet it was voluntary. I did it. I intensified the feeling on purpose...  I came up with sleep paralysis and warning signs of a heart attack. But I might need some professional help.

[Balthier]

Edit:I'm going to attempt to get the feeling back, maybe come back with a little better description. Let's all hope my heart doesn't stop doing it.

[Balthier]

Edit: I'm going to attempt to get the feeling back by following the same train of thought and relatively the same circumstances. Let's all hope I don't die.