Minecraft (Not Responding) Error

Everytime I try to launch Minecraft, it will either get a not responding error or will load in, but whenever I go to join a world of my own or a server, it gets the not responding thing again. It is not my computer because I have tried all of the fixes and used my virus protection to scan my entire computer and nothing came up. This is the only thing affected with this not responding error. My youtube channel is all about this game so please help me fix!