Folders missing from Lightroom/still in Finder

I imported photos today, and upon my first attempt, it wouldn't import. I ended up going in Finder, creating a folder (on my external drive where I keep my photos and catalog) and subfolder there, then importing them using Lightroom. After creating the folder for them in Finder (as opposed to creating it upon import in Lightroom), all of my other folders that I keep on that external drive with the catalog disappeared from Lightroom. The new folder I created is there, all by itself. The photos are not in the "All Photographs" folder. They are not listed under the parent folder (which is the name of the external hard drive). I cannot right click on the external drive name folder to synchronize. I've rebooted a few times. The image folders are all still there in Finder, as is the catalog.  I'm at a loss, can someone help?