Yesterday (or possibly the day before) I created a new project with the aim of redrafting a story I gave up on a while ago. I planned out several chapters and scenes, set up metadata, and today wrote 3000 words. Then my PC (Win 8.1) crashed. When I started it back up and opened Scrivener, it opened my old project. I tried to open the new one and it gave the warning message something like ‘this is already open. this may be because it did not close correctly. if you’re sure it’s not open somewhere else press continue, otherwise make a copy’. Because I could see there wasn’t any other copy open, I pressed continue. And found a completely empty project - no planning, no words. The file was even just called ‘project.scriv’ in Windows Explorer. And of course when I went to close it it auto-saved.
I’m hoping that my words/scenes are still buried somewhere but I can’t see them… any advice on getting my project back? 
Update: I found my words! Project file has somehow got very confused and is doing nothing, but buried in Files folder is all the writing I did today 
The binder is controlled by the “project.scrivx” file that’s contained in the project’s .scriv folder; it’s the file with the yellow Scrivener icon that you select to open the project. It lists the titles of the binder items and contains meta-data like the label and status settings, but it doesn’t contain the text of the items. That is saved as individual files (per binder item) in the project folder’s Files\Docs folder, and the binder file essentially links to them. It sounds like your project binder file got corrupted when the computer crashed, so although the other files are still safely in the project, they’re not being listed in the project’s binder.
Had you just created this project and done all the work in one day? If not, and you still have your default auto-backup settings, you probably have a backup you could restore. It may not contain everything, but it might help get you back up to speed more quickly. In Tools > Options, go to the Backup tab, then click the button to open your backups folder and check there for the most recent backup for this project from before the crash. If you have something, copy the file to your desktop, extract the backup, then open that side-by-side with your current copy of the project. You can drag and drop from one binder to another to copy items from one project to the other. When you’re finished, you can close and delete the copy that you don’t need any longer.