New ipad synced with icloud and now lost my new camera roll.

So I used to own an ipad and backed up all my photos n things on icloud, I broke that ipad and have recently bought a new one.  Today is the first time I have plugged it into my laptop and it has synced with the icloud account with all my old photos on and so now I have lost the camera roll that I had on my new ipad and transferred all the photos from my old ipad onto this new one.

This is really not good!

Please tell me there is a way I can undo the sync so that I can get my camera roll from the new ipad back!?