Lagging issues. Anyone?

Recently I’ve noticed, after 4th upgrade, that occasionally mob movement lags and cuts, and my mining tools swing repeatedly but don’t hit the stone, and don’t make the “tink” sound, or I use my axe to break up boxes and barrels and they just vanish for many seconds then reappear and then actually break after I’ve stopped hitting them, also I’m finding that certain chests in certain locations, (mostly underground) don’t open smoothly, or don’t close when I am done using them.

Anyone else experiencing this? Any suggestions on how to remedy it? My internet connection is extremely fast so I’m sure it’s not that.