Lost playlists, Albums, Songs etc on Music app in iOS 8.4
I have just updated my iPad to iOS 8.4. I've set up the new Music app but I seem to have lost all my playlists, songs, albums etc. The only things showing are 'Recently Added' and 'Purchased Music which amount to the same thing. Where is the rest of my music and where are my playlists? I will certainly not be amused if they have all disappeared! I'd be grateful for any help you can give me.
iPad (4th gen) Wi-Fi, iOS 8.4, null