Minecraft lag?

I am having problems with tick lag on this one specific singleplayer world that is unfortunately also my main world. When I break blocks, especially if those blocks take a long time to break, they reappear and take several seconds to finally drop.

The movements of all mobs are laggy and weird, and the sky seems to jump around or slingshot slightly every few seconds. I have my graphics settings pretty low, but I can’t put my render distance much lower without dealing with this glitch of mobs not spawning.

The world where I’m having these problems is a pretty big one, and I’m worried that the amount of exploring I’ve done might be effecting it. I can post screenshots of my setting and the f3 thing if that would help. Would optifine help with this? If so is there any estimate of when it’ll be updated?