Windows 10 has a bad habit if getting a corrupt profile and starting with a temporary profile.
If you never customized your background or theme it often looks the same as your regular profile except nothing you save will be kept.

Are your browser bookmarks still there? Are your files still there? I.e. pictures you downloaded or documents you typed up and saved?

If this is what is happening, your original profile is still there along with it's files but the temporary profile is re-created every time you reboot so anything you save to the desktop, documents, or any folder in the temp profile will be erased.