If you had been writing/updating Windows sticky notes for last few days, then there is a chance that your notes may be inside Notezilla backup.
The video above assumes that you have access to Notezilla . However, if you don't then you can open the Notezilla data folder by opening the folder %appdata%\Conceptworld\Notezilla and follow the instructions given in the video. To do this, copy this path %appdata%\Conceptworld\Notezilla and run from start menu or open in Windows Explorer.