computer doing strange things.

[hwally]

I have an HP 18, windows 8.1, Malwarebytes premium, Avast premium.  All programs are up to date.  For about a month my computer has been doing unusual things.  At one point Malwarebytes was turned off and after consulting with members of this forum I removed and reinstalled it.  I've also turned on my computer and, before the desktop appeared, encountered a live, full screen view of myself sitting in front of the computer.  Last night my keyboard wouldn't enter text when I typed.  I signed  out and when I tried to sign in again (this is a non-administrative account) I couldn't.  It said I was locked out.  I signed in to Admin and ran a full scan on Malwarebytes.  It showed no threats.  I also ran a full scan with Avast and got no threats.  I signed out of Admin and shut the computer down.  This morning when I booted up the computer it showed my user account as being signed in.  I didn't enter the user account I signed into admin and ran Malwarebytes and Avast again.  No threats.  Any ideas?  Is there any other type of security software I should be running?  One more thing I reset the computer to an earlier time after I reinstalled Malwarebytes.   

[Firefox]

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