The project in your screenshot is a “Playlist Only” project. When you push play in the player, it is playing the playlist clips in order. Some people don’t even realize that you can make a project using only the playlist.
If you had clips in your project before, they are gone now. I do not know how that can happen. But I hope you have been saving backups of your project. If you have not, consider using File > Backup and Save for your next project.
