Gui glitch

I decided to fill a 20by 20 by 20 area with stone with a command block to test a pickaxe(in my creative workd) it filled the area fine. next I used redstone blocks and I noticed that the blocks went invisible for a sec but otherwise normal. Then I filled slime blocks, it took a while to fill bUT it did it and then I noticed my gui suddenly dissappeared(it reappears for a short time upon reloading the world). Chunks momentarily go invisible if I load them,no menus or interface shows but is still functional,updated blocks go invisible, and all entities are invisible along with particles. note that I can still place blocks, move (with the invisible arrow buttons), and attack also turning on and off hide gui does not help nor deleting minecraft all together and it only affects that one world. Now, odly as I was writing this report and went to take a screen shot the world seems to be okay. No idea what justo happened