Died when coming back in the game.

When I saved and left the game I was in a bedroom in the house I built. I was safe and nothing that could harm me was near. When I came back in the game it said I had died and I was outside next to the house I had built and I had nothing left on me or in my inventory also none of my things where near me. I still do not have anything of mine as I could not find it any where. I am getting very upset as it took me awhile to be able to get all the things I had.