When I do that I can only make the panels larger. There is something basic wrong. All of the menu items on the top left should be there but only 4 are visible. My other programs display is normal as it has been. It is as if I changed the resolution. I see no option in lightroom to make such a change. Lightroom on another computer is fine. Photoshop looks fine.
This is probably a setting in Windows OS to set the resolution of the Lightroom App. Right click the Lightroom shortcut and see what the settings are, probably disable screen scaling for Lightroom.