Default Lost all my camera picture

Hello,

I gave my friend my phone to take some pictures and when I got it back I checked the camera folder in the Gallery and it had only the few picture that he took, now I'm sure that he didn't delete it because he don't know how to use it.
I restored a backup that I took it using Rom Manager but that didn't help, when I open the Gallery, I see my 350 old pics than the total camera pics reduced to 120 and than I only see the new pics that my friend took. (this happens if few seconds when the phone is loading pics)

I can't understand this issue, can you please help me?

Best regards