Ok your master file table has probably got corrupted.
a data recovery service or program is your only hope now.
If you try a program I'd use the freezer trick first
Be aware that most "shareware" recovery programs only show you what you could recover with the full version. And to get the full version you have to pay in $ with a credit card, so I hope you have one and not just a debt card.
if you want a good program I'd recogmend GetDataBack but I'm sure others will recogmend other programs