Unable to sync music from itunes to iphone 5

Was trying to sync a few albums onto my iphone the otehr night..  Everything seemed fine, selected what I wanted syncd, looked at iphone and it had the 2 arrows rotating in a circle indicating that something was being syncd.  However nothing happened.  Then itunes all of a sudden shut down and restarted, only showing the music I had purchased via itunes.  None of my pre iphone/itunes library was shown.

Managed to get library back to normal and tried again.  But for some reason when I went to add the music, had no option to do so.

Normally the way I add music to iphone is select iphone in top right hand corner... then 'On This Iphone'.... It now shows all the music on iphone.  This is where something aint right.  Above the list of music on iphone, there is normally an option on the far right hand side saying 'Add To'  this option is now gone.

Also, the music I was trying to sync onto iphone HAS went on to the phone, but is greyed out and am unable to play it or delete it from iphone.

Both itunes and iphone 5 are the most up to date versions.  I also uninstalled/ reinstalled itunes on to my laptop, but didnt help at all.

Hope I have given all info needed, I have not changed any settings within itunes, so am at a loss as to how/why this has happened.