Not looking good after doing some search on Google.

(ANS) If you have received an error message saying "internal HDD hard error" then this tends to strongly suggest that your hard disk drive is in the process of going to fail. Hard drives usually last many thousands of hours if given good conditions such as constant temperature range and that the disk drive isn't worked too death or over used.

However, HDD do fail eventually both at a surface level i.e. some tracks or sectors or segments fail magnetically. Drives can also fail electronically too.
Its not so much IF a drive will fail more when a drive will fail, its a likely event not an unlikely event. This is why ALL good computer systems in business have built in fault or failure tolerant systems so drives can be hot swapped when they fail without bringing down an entire server or cluster of servers.

**You could (can) run software diagnostics over the disk drive if it hasn't actually gone yet?

**YES! if the HDD has failed then its quite appropriate that you would see a BSD (blue screen of death), as a disk failure would corrupt or damage system files or drivers that are critical to windows. Thus giving you a stop error or critical error of the operating system.

**My guess is that this drive has failed which means you need a brand new HDD and will need to re-install literally everything from windows upwards. You will have lost ALL your data & personal files if you didn't make backups?