computer types \\\\ by itself... think I have a shneaky virus/ trojan

when I click on textboxes, my laptop automatically tries to put in a bunch of back sla\shes.  I'm struggling right now to delete them and type.  I ran a scan, nothing.  made it a little more thorough in the settings, still, nothing.  I know it's not a hardware issue, my keyboard is fine.  tried different ones.  \\\\h\el\p\\\ \\p\\\l\\\\\ea\s\e!!!!