Pausing not working in Survival

I paused my game (not inventory, in single player surivial), and the game stopped, but when I unpaused it, its like time fast forwarded an equal amount of time I had the game paused, the sky quickly shifted to match the passage of time, and a zombie, which i did not notice/hear before, killed me instantly (I was at least at half health, probably more, on easy difiiculty), as if he was attacking me the whole time I was paused, but it didn't affect my character till I unpaused the game. Also all my equipment (I returned quickly in Creative mode because of the bug) had despawned, presumably it had already despawned when I unpaused the game.