I agree with PPs, I think you had a m/c (depending on how far along you would have been it could have also been a chemical pg). As for starting to try again, because you didn't need a d&c, I
think (I'm not a doctor, so this is not medical advice, just what I've picked up on) that you can start trying again as soon as you are emotionally ready. I would still go see your doctor anyway.
Sorry to hear about this.

I hope you get your sticky bean soon!