Problems need help

Hello guys

I have a strange problem that occured yesterday when i was trying to make my name fancy and my settings all reset its like i downloaded the game again.

I made all my settings and go into a server to play v3royal block server all other people were lagging like teleport but not me
i mean they lag in my screen not server lags or some thing like that and i was wondering if i did some thing wrong

never had this problem before and i don't know how to fix it it's unplayable can't make 1 hook