Stuck on "Repairing disk errors" screen on Windows 8.1

[sanicisforlifebruhgofast]

Every time I turn my pc on it boots into this "Repairing disk errors" screen, and I don't know why, as my pc was operating just fine before shutting it down normally.
It's stuck there, I let it do its thing overnight and 8 hours later it was still on the same exact screen.
I tried booting from my USB stick, which has an Windows 8 installer on it, and no success. I even tried booting into the EFI Shell a few times but nothing, it always goes straight to Automatic Repair, which automatically goes to the Repairing disk errors screen and there really is nothing I can do other than accessing the bios.
How can I fix this?

Also, I have some important stuff on my HD so I'd avoid installing a new fresh OS or getting a new drive.

 

[RolandJS]

You might have to get a local data recovery person involved, helping you, walking you, through whatever process s/he recommends at this point.