I've seen weird and scary things during this state, but wondered if it was TRUE sleep paralysis or just a lucid-false-awakening-nightmare. Because although I found it extremely difficult to move, I eventually could. Sometimes just an arm only. And If/When I could stand up I would stagger to my bedroom door as if drunk, feeling a strong desire to collapse to the ground and even once felt as though a large elastic band was stuck to my back attaching me to my bed. It was like my body was saying, "lay down and go back to sleep." Every fiber of my 'dream body' was saying that. But as soon as I left the 'room', I was suddenly free and able to roam freely and lucidly. And they were always more vivid than other lucid dreams with a sense of having a body.
My theory is that I was almost awake and could sense, or was at least aware of, my physical body, but was still in a lucid dream state. So it is a weird sensation for the mind to handle. But after time, like anything else, I got use to it and seldom get it anymore. Or If I feel one coming on, I just think happy thoughts and ignore it.
If we all lucid dreamed this world would be a better place.