I experienced some very weird 'half asleep' disturbances?

Basically last night I woke up and trying to doze off again, almost half conscious, my body started making really odd movement, My fingers started to 'mexican waves', my arms were moving in a wavelike motion, my wrist were twisting and basically at some points my whole body was involved. At some pointmy limbs were kinda going upwards almost as if levitating. Now, if I thought of it, I could control my body and make the whole thing stop, but when I stop thinking I would go into full motion again and then I would stop it. Im pretty sure it wasn't just an odd dream, but at some points, it felt like I 'hade' to move my bodies in certain ways, without really trying (it was that weird!). Nothing like this has ever happened to me, and im not on drugs or anything! I am taking meds though, but have been for at least 2-3 months and haven't had any side affects so for. It almost felt like something else was commanding my body, but I could stop it if i wished. I am not superstitious, I don't want to be told it was a ghost or something, Im just wondering if anyone will be farmiliar with it in the sciencetific sense, or experienced anything simular. It wasn't a frightening experience, just slightly disconcerting.