Keeps freezing, shuts down, deleted some stuff I had.

I keep joining at my last save, which is inside the nether. But when I go back in the overwold, the progress I had done is there but not all. Like the door is open when I remember I had it closed. Yet the builds I had is like they never existed. My sniffer is deleted???? Keeps freezing and shuts down when I press esp or L. AND EVERYTIME I press esp, or L, it freezes and never gets the opportinuty to save the game. Same thing happends everytime I try to join. Inside the nether, insane lag, press esp and freezes. My internet is fine. (Okay what. Now out of the pocket it stopped freezing. My sniffer is still deleted.)