My ctrl and right-shift keys are not responding, though they still work in a VMware window. Numlock doesn't work. A held-down key does not repeat. clicking in a field in another window does not make that window active.

Can I clear whatever's making it sick without rebooting?

It started (approximately?) when my full-screen VMWare workstation instance on Desktop 2 was missing and found as a small window on Desktop 4. It moved by itself or I accidentally entered a strange command while working on Desktop 1?

Linux Mint 17.1 Rebeca, standard Cinnamon desktop.