Why do I have a different FCCID, ICCID

I had a 5.0 IOS, and I wanted to get it unlocked and jail break and I gave it to a guy. When my iphone is returned, the FCCID and ICCID on the back of my phone and the regulatory section, setting->general-> about-> regulatory, become different. I also felt something fishy because when he gave me the phone, there were like 300 contacts on the contact list, of which none of them that I know. I know he didn't save them on my phone on that given time. I am thinking that he might have changed something on my phone. Could you guys help me figure out what is going on? Thank you so much.