Hello Anna Lee, thanks for posting this in our community. I completely understand how frustrating and worrying this situation must be, especially knowing how important your photos and files are to you. You're not alone, and we're here to help.
Just a quick note: security questions are usually associated with local accounts, not Microsoft accounts. If you've confirmed that your PC is linked to a Microsoft account, please make sure your device is connected to the internet, as Microsoft account login requires an active connection to verify your credentials.
Sometimes, the issue might be caused by keyboard layout mismatches. On the login screen, try clicking the Ease of Access icon in the bottom-right corner and select the On-Screen Keyboard. Then, carefully type your password using that virtual keyboard to rule out any input errors.
Kind regards,
John Oli