ok i'm mining in survival mode and i mine some iron ore. Then there is no drops. All of a sudden Minecraft rewinds to the point when i was about to mine iron ore

I was mining ore for a long time after that then I was Iron Ore and i wasn't getting anything from it e.g. Iron Ore. Then it rewinding to a time when I was about mine that stem of iron ore and got the iron ore i mined before