Nope, it's gone. I've done that many, many, MANY times, screaming and yelling at my computer.
Here's a few tips: If you like what you see, then SAVE!!! Save often. Use SAVE AS if you want to have a history to fall back onto.
I'm not going to say I didslike the 3D stuff. I will only say I have troubles with it, but I can use it.
Another option: Control-Z is still your buddy. Not sure how many levels of UNDO you have, but you do have at least ONE.
So, been there, done that, started over many, many MANY times.