Items Vanishing / Item Frame Sound Glitch / Pets appearing next to me

All day I've had cats and birds that I've tamed and set to sit have been appearing next to me and not listening when i tell them to sit again. Also, all the item frames make an extremely annoying thumping sound when they have an item on them, all the paintings I've placed have vanished along with a few of my very important items have disappeared without a trace.