There are a number of disk recovery applications, it appears this issue may be with a corrupted but recoverable file system. If that's the case, you may be able to recover your lost data. The second point would be this: Backup! You are a professional photographer, you should be maintaining backups!
I would like to point out something here though, Nice as many aspects of Macs are, the HSF+ Journal file system can't match Microsoft's NTFS system for removable drives. NTFS was designed to handle sudden removal, no notification writes/failures gracefully, and HFS+ still doesn't. Try it. Walk up to a windows machine, plug in an NTFS formated thumb drive, start writing a file to it, and yank it out midway, then plug it back in after a minute or so. See that? The file system on the drive is fine. Your file might not have written, but the file system itself and all the other files are fine - with a no notice, mid-write removal. Apple really needs to step up to that, the business of having to "eject" things from the system before disconnecting them is really obsolete, and realistically dangerous. And this extends to other bus type devices than drives.