My computer shut down and i had not saved my work yet

Sometimes if my computer goes bonkers... which is rarely or I shut down without thinking (also happens rarely).  Then when I restart my computer and then Illustrator... it will start with a recovery file.

If for some reason it did not do this... then most likely it is gone.

I am so sorry.  I know this is really frustrating when this happens.  You feel like yanking out all your hair especially if spent several hours on a design.

I always try to save in steps.  I work for a little bit and save the file as 'Illustration_a'.  Then I continue and once I hit a significant change I save as 'Illustration_b'.  This continues until I am finished, then I save it as 'Illustration_final'. 

In a way, it is like playing a video game. In many games, you save checkpoints or how far you have progressed in the game so you do not have to start from square one. Also if you save in stages, then if you make a mistake you can open up the last file and go from there.  And if you save in stages you can go back later and create screenshots for your portfolio.  I do this and showcase projects in stages.  Which looks cool when describing how you created a final graphic.

Yes, your work is gone.

And the recovery feature does not "auto save" anyway. It's a recovery file. It needs to be processed by Illustrator after a crash. It won't protect you from other things as crashes. And it's not guaranteed to work.

Save your files. Save early. Save often. Save different versions in different files.

And if you can't remember to save, get the plugin Autosaviour to remind you of saving.