Kane signed for the Canaries on Friday.
"Friday was a long old night and I'm glad to get the deal done and obviously it's a great opportunity for me," said Kane, who scored seven goals in 22 second tier appearances at Millwall last season - winning the club's young player of the year award in the process.
"It was one of those that was a bit up and down. One minute I was going and then the next minute I thought I wasn't, but that's deadline day I guess. I got the call at about half nine to say it was going to be pushed through so I got myself down to the training ground and got it done."