duped inventory on death

Sorry not sure if i can explain this well but i went mining and found a cave well an enderman killed me but i tried to take advantage of the auto save so i didn't loose my stuff i closed out of the game and returned to the xbox dashboard hoping it would put me back to the last auto save but instead it put me right next to where i died but i had all my items and my items were on the ground as well so i went from one diamond pickaxe to two and instead of 17 pieces of tnt i now have 34 ect from 28 iron ore to 56 im sure you get the point im not sure if this was helpful sorry