It sounds like you did a factory reset. If so, when it resets itself back to its out-of-the-box settings, you can sign in with your Gmail account and at least get your contacts back. If you didn't use an app to back up things like SMS, you'll lose those. You'll have to manually put your settings and widgets back to the way you had them. Hopefully all your pics were saved to your SD card, in which case, they'll still be there. And last, you'll have to reinstall your apps from the Play Store.
On the bright side, your phone should run clean and smooth now!