Framerate is awful when exiting chests/using crafting interfaces, and taking damage

While I was playing I was exiting chests to get ready for a nether haul when my fps just bugged out and lagged the game causing horrible delay. After that I farmed some animals for food and as I was striking a cow the same fps drop. It happened again when on said nether excursion when taking damage from some mamga cubes I lagged with every hit from them causing instant death and a bountiful trip ruined after a lot of hard work and effort. To anyone that says this is not a bug, to them I say i tried to tweak the settings on every fps that was available and to no avail at all, even below 50 fps this happens. My advice is to fix the fps and video settings to be more optimal and to where I can set my fps to either low, medium, or high.(would've been smart to do that from the beginning like every other game)