Blocks are glitchy.

When I place some blocks after placing barrier blocks, they disappear too. Actually they don't even show themselves. Also when I place some dark prismarine blocks and break them, they stay there but they act as if they're not. When I give myself blocks, the item jumps out of my inventory and then back into it. I clicked stone buttons on the command block and they either got stuck as being clicked or were clicked for a VERY long time.