Entering the nether when the difficult is locked in NORMAL sometimes goes crazy the world

Entered the nether and it went crazy, then returned to the overworld with actually the same problem

What I expected to happen was...:
The nether would load normally

What actually happened was...:
An are from the nether went crazy putting random blocks,
When returned to the Overworld it happened the same

Steps to Reproduce:
1. I was playing normally, with no cheats and locked the difficulty to NORMAL
2. got diamonds and entered the nether for the first time. (picture 1)
3. Returned to the overworld (picture 2)

(OPENING AGAIN THE WORLD DOESN'T FIX THE PROBLEM)