I bought an iPhone 6 and I gave my old iPhone (the 5c) to my niece. Had it done at the AT&T store. The sales rep changed her # to my old phone and my old # to my new phone. I jumped on the iCloud and was able to transfer all photos, messages, etc onto my new iPhone.

the first time my niece plugs in her iPhone 5c (which was my old iPhone), all of a sudden, all of her contacts replace mine on my iPhone 6 and now we both have the same contacts - hers.

I logged into the iCloud on my laptop and all that's there is her contacts. Mine aren't there. Did I lose all my contacts? Is there any way I can get them back?

All my text messages are still on my new phone, but the vast majority of them only list a phone # not a name. So maybe I can figure out (in most cases) who these texts were with but it's still a major chore to re-enter everyone's name - not to mention other things I kept in my contacts for my friends such as email address and street address (all of which I will have to ask for or remember).

Is there anything I can do?