When I was going onto my creative world, there were gaping holes(16x16) in most chunks going down to stone (in redstone ready superflat). Most of my builds were gone, and all the entities were gone. When I explored, I realized just outside of my render distance there was a giant gaping hole that was 10 chunks thick, surrounding my area that I build in. Just past the gaping hole, the chunks seemed to be not destroyed.
I went into the nether... Oh gosh it was weird. Every chunk was excavated, from top bedrock to bottom bedrock in a 16x16 CHUNK area.
There was random lava blocks everywhere(floating ones that weren't there before). Everything was... Everything was like it's biome name.
I went to the end and everything was normal in the end. How nice.

What I expected was:
To go into my creative world.

What actually happened was:
My world had holes down to stone in most chunks, all entities were gone, and a giant hole went around my building area.

Steps to replicate:
I don't know.
Nobody else seems to have this.

Other notes:
This happened in creative single player. The odd thing is, some of my builds are gone with parts that weren't on the odd chunks still missing. One of my builds was on one of the chunks that was destroyed, but all the water was still there, in the chunks that had holes in them. I made this world in 14w21a, and I really don't expect you to believe me for the nature of this and the following sentence.
I have no screenshots because I don't know how to post them.