MAJOR ERROR! Not all photos transferred when I updated catalog to LRC 10.0

I seem to have had a MAJOR error happen when I updated my catalog to LRC 10.0. It did not bring in some of my 2018 photos, or ANY of the 2019 and 2020 photos. It also seems to have lost all my Smart Collections, Flags, and except for some Green color labels, all the other color labels I had. I'm also missing vast amounts of keywords, and Develop settings on corrected photos, along with Snapshots. I should have had a couple dozen in the Quick Collection that I was about to export. Also, I had flagged as Rejected nearly a hundred photos and was planning to continue and cull out all of them, but have no flags on any photos I've checked. It's not even as if it read a really old catalog, because I've been working my photos for years. It's possible the error happened when I first tried to update to v10 a few days ago - it seemed that everything hung and LRC shut itself down, possibly before completing the process (I was working in another room, so I don't know exactly what happened, and I only got back to it today).

I've attached a screen shot showing that there are no Smart Collections. The selected photo should have had a white flag and should have been showing that Develop adjustments had been made. The one with the Photo Missing tag should not have shown up again - it had been deleted from the catalog and the hard drive. My keywords are missing. The bird should have been in my Birds Smart Collection.