I backed my phone up and it deleted everything on it

yesterday I plugged my phone in on my computer to sync the music that I had on iTunes to my phone and it said that I had to back my phone up before I did it. I did and my phone turned off and back on and whe. It turned back on it said update successful and all my pictures,contact, and texts were delete. I tried to restore it from the back up but so far nothing has worked and the music didn't even sync. What should I do because all those pictures and videos ment a lot to me.