The man's girlfriend phoned him on Monday morning and told him to check his ticket because she had "a feeling", so he headed straight to the nearest Lotto store.
"The guy at the Lotto store told me I'd won $14,000 and I thought 'that's amazing.' I was so excited that I phoned my girlfriend straight away to tell her," the winner said.
"While I was on the phone, the guy said to me 'I'm really sorry, I've made a mistake' and straight away my stomach dropped.
"Then he said, 'you've actually won $14 million'.
"I was blown away - I think we were both blown away," he said.
The man also told family members "and they're all over the moon".
"I also told a few people I met at the airport - the security guard and other passengers on the plane. I was acting so erratically I felt like I needed to justify my behaviour."
"I had coins in my pocket going through the metal detector and the guard pulled me aside for extra screening. I said to the guy, 'sorry mate, I've just won Lotto, I'm going to collect my prize - I don't know what I'm doing.'
"Then once I got on the plane, I was sitting in the wrong seat so I had to move and explain to the people sitting next to me why I was so confused. I said, 'I've just won Lotto - I'm freaking out'."
Asked if he had planned to quit his job now that his future was financially secure he said "yes, I already have".
"I phoned up and said I wouldn't be coming back in as soon as I found out."
"I'm sure I'll find other productive ways to fill in my days beyond the 8 to 5. I like working with my hands so might build myself a workshop to potter around in or do some volunteering as well now I have the time."
The man, whose biggest previous Lotto win was "maybe $24 or $28" said he always wanted "a house with five acres around it and a dog".
"Lots of ideas are running through my mind - anything is possible for me now. I'll probably still buy a house, and I want to help all of my kids get houses too."
The winning ticket was sold at the Ashburton Countdown Lotto. The prize was made up of $13,395,864 from Powerball first division and $1 million from Lotto first division.
It is the fourth largest prize ever won in the South Island and the 19th largest lottery prize ever win in New Zealand.