Well, I don't have any clues to why this happened to me but I'm pretty sure It's Forge that is causing this problem.
I was playing my new 1.16.1 survival normally, mining, and suddenly i stopped getting cobblestones, at first I thought I was with my inventory full, but I wasn't.
Then I realised the items were re-dropping, every second the items kept coming back to the place their block was.
I couldn't get any items, even the ones i dropped just to test.
I closed and opened the world again, restarted the game, nothing worked.
Only when I started it without forge they stopped glitching.
I wasn't using any mods besides Optifine so there is no way that this was not caused by Forge
