I also had this same problem... twice. It was extremely angering. The first time it happened, I wasn't sure whether or not I deleted it or if it was lost. Later on, I played on another world and the same thing happened. I spent many hours on both worlds, and I am very disappointed. I don't see this being discussed a lot, so I'm really glad you reported this; now I know I'm not the only one. I hope this gets resolved soon, because it makes me not want to play Minecraft.
Michael Skipper
I also had this same problem... twice. It was extremely angering. The first time it happened, I wasn't sure whether or not I deleted it or if it was lost. Later on, I played on another world and the same thing happened. I spent many hours on both worlds, and I am very disappointed. I don't see this being discussed a lot, so I'm really glad you reported this; now I know I'm not the only one. I hope this gets resolved soon, because it makes me not want to play Minecraft.