Recently I changed to a windows 8 laptop

Guy's I am a 70 year old pens and i bought an HP Laptop and paid extra money to Curry's to have everything transferred over from Samsung to HP this was done yesterday and I brought It home . All I was really Interested In was making sure that Spotify, Windows Media and finally ITunes went over successfully.

To my utter dismay, I found I was missing approx 1200 recently bought tracks, now I had seen all of these prior In Songs, Albums and Artists so I thought how can they be missing, eventually I found the buggers In a column called Account, called naturally Purchases, I tried to download them all and the system said I was not authorised which I found odd because I'd paid and as said seen them successfully downloaded. Could someone tell me what to do next.

Cheers

Pensioner Pete.