Instead of losing my work, can I correct it (or any part) with newer data?
What newer data? Are these new catalogs?
Did you look in the trash/recycle bin for your files?
In general, if you delete your catalog file (the *.LRCAT file), and you don't have a backup, you're in big trouble. You might still be able to recover some of your work if you chose to write the metadata to XMP (this does not happen by default), but even in that case, there are items in the catalog that are not saved in this manner and so cannot be recovered in this manner. You might also want to try something called an "undelete utility program" to try to recover your catalog files as a last resort.