world glitching/player glitching both in realms and single player

not sure what to describe, but i just updated to 1.8 and created a single player world walked around a bit then quit to main menu n went to my realms world, about 5 min in my character started to "glitch out" super extending all the body parts except the right arm and the head, thinking it was something to do with the realm i quit and went back to single player world and experienced the same thing with my character but this time a section of my world was bugging out, i have some pics attached