It messed up my world.

It to upload my 'Path To Parkour' map with no trouble.

It got uploaded with weird structures.

1. Make a new world.
2. Place down at least 30 iron, gold and diamond blocks.
3. Put a brick staircase on each one.
4. Put ladders on each one.
5. Re-upload the world at least 10 times (I'd reccomend a few more).
6. Wait at least half a year.
7. Look at what herobrine did to your world.