It was obviously SP

It doesn't always bring hallucinations. Especially if you can keep your mind clear during it. I had many SPs, but some of them had no hallucinations at all.

You also need to know that it's possible to seamlessly transition into a dream from SP and you'll still be laying the same way as in real... maybe you really moved, but it was in the dream. Once you tried again, you were probably awake again and SP wouldn't let you.
Or you just felt like you moved... quite possible, i had experiences like that.