It might be possibly the onset if your dream focus. You might have been shifting focus from real into dream focus. Thus these sensations.

One more thing. It is not always the easiest thing to do, to separate yourself from your real body. At first, You really dont know, which body you are moving as they are aligned and sharing the same relative positions. One of the nicer exits worth trying would be to inject yourself into a fantasy which might pop up, so you teleport your dream body away from your real body.

The second approach would be to construct your dream body elsewhere using your memory.

In both cases teleporting yourself away from your body is essential, because that way you dint have to deal with the dream body paralysis which you worked so hard to induce.

Good luck, have fun