Minecraft updated for me today to 1.13.34.70 and after loading up my save from Sunday, a lot of blocks are now pink and black. This only seems to apply to the default texture pack as when i change it to the natural texture pack, everything appears normal.

The other thing i have noticed, is that I do not get all sounds e.g. walking, i get no sounds but if a chicken clucks, i hear it. This applies to any texture pack.

Also, sometimes, text in the menus go really strange and I have included a photo of this.