Ok so I got into the single boot user mode and ran fsck - f to check the HDD. It said the HDD is OK, but when I run the sudo diskutil RepairDisk /Volumes/Whizdrive the thing spits out this error:
dyld: NSLinkModule() error
dyld: symbol not found: freopen
Referenced from: /System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation
Expected in: /use/lib/libSystem.B.dylib
Trace/BPT trap
I am very confused with this, as I only have a limited knowledge of linnux ( which is how I knew to try diskutil command ), and next to no idea how to use Unnix ( Mac )