I have experienced this feeling before throughout my whole body but I was told that you kinda have to think of your astral body as rolling out and away from your physical. You may also try to make your astral body float above your physical body but make sure you are "in" your astral body. This is what trips me is I can't figure out how to successfully roll/float out without distracting myself plus I can't see anything too well as I try to escape.
The red lights can be a simbol for the phase and as for your meditation your speaking of, i think in that meditation your clambing a ledder or sometimes a rope, its a very common meditations, you didnt give me the complet details so i cant be sure, But for every meditation 2 things matter 1.Autinticity 2.faith.. Put faith in yourself and may you get sucess