I was mining and was running into a bunch of dirt and gravel so I changed direction. As soon as I started making the new tunnel I started to move weird. It was like walking through water that was moving in all directions. Anything I mined moved weird too. I left the new tunnel and everything was normal, so I went back in and it went back to the weirdness. I thought I had discovered some pocket of depressed gravity at first. Anyway I continued mining, collecting my first diamonds and my first gold until I hit an area where I started vibrating and counldn't move. I can still look around. I mined all around me to try and make myself fall but I just floated. I'm sitting here now in a hollow sphere floating right in the middle, vibrating, and unable to move.