Odd Experience:

I just attempted sleep breathing while lying flat on my back and had something odd happen. After a certain amount of time my hands and forearms started to raise upwards with very very little effort on my part (it started on its own). Nothing else was raising and after my forearms were fully upright ,with my hands still a little limp, I opened my eyes. I performed multiple reality checks but all of them worked out and I knew I wasn't dreaming. Is there anything I can do from this point to put myself in a lucid dream? Also what was this?