https://www.youtube.com/watch?v=hYme1yI2Dpc&feature=youtu.be
it's probably always the "freefall" bug, only this time it "hit" a wall instead of the floor. my advice is to update the browser or whatever because when these bugs happen, they happen only to the single player. so it's not a problem related to the map or even to the server. (so it seems from the circumstances found so far)