I've had a melt down !

For several years now I have used my "Lightroom" software to run and store my  image catalogue which I keep on two external hard drives. All was well until a couple of days ago when changing my external disc for two larger disc when all images suddenly  disappeared ! ! !  Thousend of images gone!
After sitting looking at the machine for several minutes,  drum stuck
I have downloaded some image rescue software which has rescued several thousand images and I am now left with the job of sorting these into some resemblance of order and see what, if any have been lost permently
              
      I think its a subtle way for my computer telling me I'm getting old