Chunks load slow, world generation slow, and mobs despawn right in front of player

Here we go again with more bugs I found. When I created a world, it took about 5 minutes to load in and when I did finally load in, it was almost nearing night. I tried to get wood and such, but the chunks loaded so slowly in the Infinite world, I thought it was an Old world. I got a bed and slept, then when I woke up, a sheep despawned right next to me. The chunks were still oading slowly, so slow that I could see caves below me.