Ok so I regularly play Minecraft (like at least 2 or 3 times a day) and this morning I tried to get on, but it was different. It had said I didn't download that game. It had just not logged me in. I logged on and clocked n single player mode, but it didn't show ANY of my worlds. It didn't show any of my servers either. Also, it changed all my settings to default and deleted my texture packs and my skin. I have no idea what happened. I have yet to do anything to try to fix it because I haven't the slightest idea what to do.