Descending Preformance of my Minecraft

Ok, so since December 1st (Coincedence?) my minecraft has just been seeming to decay and sort of slowly break down. On dec 1st, i started to encounter intense phantom blocks and entities, the entire 20x20 area i mined out was not droppong cobblestone so i restarted my mc and poof there was 2 chunk errors and phantom stone EVERYWHERE, placing a block anywhere would dissapear, i deleted that world because of this. on the 3rd, i started having random freezes of minecraft and forcing me to restart my computer, this happened mostly when breaking blocks that make the glass sound (glowstone glass pane etc.). and now today my minecraft refuses to launch and the loading bar simply remains white, i have tried logging out and in, making a new profile but nothing works. 😞 plz help me, i really wanna play mc (I have no mods)