LR catalog corrupted

Hi guys, something just happened to my LR catalog and it's kinda bizarre. So, I only have one catalog for all of my sessions. It's been working great for me for all these years. Today, I opened the catalog, and got the notification that it's corrupted and can't be repaired. OMG!!!! Then, I found another version of that same catalog (i.e. master catalog (1)). It was created on July 15th by nobody, and it has every sessions before July 15th. Anything after was lost. Has anyone ever experienced this?

Also, now I have another issue. Because of what just happened, now the new catalog is missing 7 sessions. My workflow is like this. I import photos from my card to LR, and send the raw files to a folder in my hard drive. Now, how do I import these raw files into the new catalog without duplicating the raw files in the exisiting folders?