I have no idea if this will help, but I too recently updated an unused Windows 7 laptop to 10. Upgrade went fine and I'm getting to like it. (Not really that different from 8.1). But I noticed that the upgrade reset several of my prior settings. For instance the TouchPad would no longer scroll. No it was not a driver issue. The upgrade had reset the TouchPad settings and the scroll option was unselected. Several other similar issues. It uninstalled my Classic shell start button. Yet I reinstalled it and it works fine. Etc.
So, before looking for driver issues you may want to use whatever F-key you use (F-7?) to switch display from laptop to external screen. Maybe the update changed that setting and switching it back may fix things.
Just a thought.
(hi kemical...... )