When trying to sleep body feels like it's floating or heavy & vibrating. if i sit up it goes away. lay back down it hits again. it lasts all night. ?

All perceptions&body: controls reside within the brain, look up & study: https://www.google.com/search?q=homonculous. Thus, while this sensation may reflect something you're initiating within your mind/brain (including not consciously aware of doing so) or a response from outside your body, all perception & interpretation is (as always) within brain/mind. Fears triggered by attempts to sleep could make sense of this.