Server Side Lag on Singleplayer

Whenever I boot up Minecraft, and go on any world, adventure map, minigame, etc. on singleplayer, I get horrible lag that is serverside. I can tell, because this does not occur on servers. It has a delay of about 5 seconds. I have tried opening to LAN, and things like hosting a server and connecting to localhost. I have tried hosting a server and having friends join it, and they get the same lag, but only on my server. I tried giving Minecraft/ the server 8GB of RAM, which did not help much. Things like plants and tall grass break instantly and without lag, But blocks and animals are 5 seconds behind. Here is footage of the supposed bug: https://www.youtube.com/watch?v=jqTY72_0Usc