What was happening to me before I began (i think) lucid dreaming?

[fleshonflesh]

I was laying down on my stomach thinking about some things when i noticed that my body was in sleep paralysis. I couldn't move and I kept having these weird feelings and at one point was hearing these strange vibrations, but during the whole time I could hear everything around me. At one point it felt like I was rolling around and sometimes it felt like my legs were being pulled up. Another strange thing that happened is I got this weird and kinda painful pulling sensation from my stomach region. But at one point I started dreaming and I was aware that I was and kinda got to control a bit of it before I lost it sadly :/ So what exactly happened to me? especially in the beginning