World generation glitch? Normal world generated with debug world

Last night I had created a world to look at what my resource pack would look like in normal generation, I left the world and created a debug world to look there also. Today I opened the natural world and bumped into new chunks, but they were generating nothing but barrier blocks at a certain level. I kept flying and stumbled upon what is the debug world contents, as you can see around it is normal world generation, the stuff I generated a few nights ago. I have no idea what could of caused this.