Things like that are perfectly normal and not evil/demonic/satanic, in my experience. Idk about the evil thoughts or entities/spirits but it's always felt natural/normal to me, like my body knew what it was doing even though i've never done that before, but i just let it happen, feels good. I have had a few experiences where it felt like there was like a kind of battle going on between a good spirit and bad spirit but i chalked it up to my own mind. But the body movements and mudras and everything, just part of the experience, it's fine
Nothing is wrong with you, it's perfectly normal ime. Also it's normal to feel like you're dying, just let yourself die, you will come back, don't fight it, just surrender and let go.