G'Day ashleigh,
'Grating' type noises from your Hard Drive means that it's more than likely about to 'spit the dummy'.
I suggest that you go the HDD's manufacturer's website; download their diagnostic tool; run it, and see if it gives 'errors'.
If it does; get all the important personal data off the drive, that you need, as soon as possible; then, replace the drive with a new one.
Sorry that it's not better news.
Kind Regards,
__________________
Dave T.
If it works, Don't fix it!
Especially if Bill Gates had anything to do with it!!