I lost Everything in Minecraft?

I play Minecraft 1.8, and I decided to download Minecraft 1.7.10.Every world that I made in Minecraft 1.8 was the same in Minecraft 1.7.10, and when I opened a survival one, EVERY ITEM is lost, including the chests and my inventory!

Guest

It Might Of Been A Glitch In The System Because The Same Thing Happened To Me, When I Updated It Fixed It, Oh And By The Way, If You Create Something Cool In Minecraft That You Want To Share Then Just Take A Screenshot By Pressing The Home Button And The Power On Button At The Same Time, Note That This Only Works On An Apple iPod, iPhone, Or iPad.

Mohammed