I I had to get my ipad2 replaced as cracked. Bought replacement in apple shop but when I got home the transfer of data that assistant did from old iPad to new was not available. How can I get this back

Can someone hep I've lost all music and photos from m ipad2 after it was replaced. Previous iPad2 dropped and cracked so had to buy new one. I also tried to sync my iPod to my computer as had photos and music there but keep getting message that my ipos all be erased as I have another account which I don't. Anyone help.