When I was younger (maybe in the range of 3 to 6,) I had these horribly real night terrors. I didn't make that word up. That's what they're called. They are terrifying, recurring nightmares that popped up in my dreams from time to time. There were two different ones that I can remember.
The only way I can explain the first one is, two elevators in one shaft and me in the middle. I was looking at myself from outside my body (or maybe through someone elses eyes.) The two masses above and below me were moving faster than anything of that size possibly could. They would both move away from me and then snap back together on me. This happened so fast that I could hardly tell what was going on. All I knew was the whole room (or wherever I was) was shaking violently and the things were repeatedly crushing me.
The second one is even harder to explain. I am in my bed sleeping, and I wake up to see this... band of energy, I guess, floating slowly around my room, twisting and turning like a snake. It moves so slowly that the motion is hardly visible, then in a split second, it is moving at super speed. Absolutely flying around my room, but never touching me.
A couple years ago, I had what I call a "residual night terror." Just like the second dream I described, but without most of the terror. I still felt fear, but I didn't scream and run around like I did when I was young. Sometimes my mom used to chase me around the house when I would randomly take off screaming in my sleep. It took a long time after that to calm me down. After a while, I'd settle down and get back into bed without ever waking up. Not fun. Luckily, I can't remember very much of it.