root@linuxcoin:/home/user# df -h
Filesystem            Size  Used Avail Use% Mounted on
aufs                  917G  227M  871G   1% /
tmpfs                 5.0M     0  5.0M   0% /lib/init/rw
tmpfs                 397M  600K  397M   1% /run
tmpfs                 5.0M     0  5.0M   0% /run/lock
tmpfs                 794M  240K  794M   1% /tmp
udev                  1.9G     0  1.9G   0% /dev
tmpfs                 794M  4.0K  794M   1% /run/shm
/dev/sdc1             1.0G  773M  251M  76% /live/image
/dev/sda2             917G  227M  871G   1% /live/cow
tmpfs                 2.0G     0  2.0G   0% /live
root@linuxcoin:/home/user# fdisk /dev/sda

Command (m for help): p

Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x4a450830

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048      206847      102400    7  HPFS/NTFS/exFAT
/dev/sda2          206848  1953521663   976657408    7  HPFS/NTFS/exFAT

Oops. I think it really wrote my HDD. What should I do?