Hi Acadia I had a similar problem with an internal drive not so long. The computer gave me a divide by zero error on the drive and we I rebooted.. poof it was nowhere to be seen. Took it to the shop for a look, and there it was, like nothing had happened. Turns out I needed to let it cool down a tad. Sometimes the best thing to do is just turn it off for a while... Failing that give it a whack :) (actually that worked once when my fan got stuck and the computer overheated. I managed to dislodge enough dust in there to get the fan going again!)

Only your mind limits yourImagination. Let it free.