|You could look into running testdisk. As I stated above, the partition may be damaged. NTFS stores the disk information in multiple places on the drive. That redundancy is suppose to make the file system hardier. That said, maybe something went wrong and there is conflicting information.|
Testdisk is designed to repair that sort of issue.
You could try a recovery program but if the drive acts as you describe it doesn't sound like you will recover much each attempt.
For what it is worth you should always maintain at least tow copies of any data you want to keep. You are now learning why. There are so many different ways you can lose your data. Your experience is just one.
Get testdisk at the link below. Be sure to read the tutorials before using.
If you want to try a free recovery program before using testdisk you can get recuva at the link below.