|Start in Safe Mode and do a System Restore to a date when all was running properly.|
Restart in Safe Mode with networking, Run Malwarebytes, remove all it finds, then update and run your antivirus program. Restart normal.
If this does not help, restart in Safe Mode with Networking and download and install your latest drivers. Check for any programs that may be installed that you did not install, uninstall anything suspicious.
You have to be a little bit crazy to keep you from going insane.