The Norwich City man set up the equaliser for Niall McGinn, before bundling home the winner as Northern Ireland got their Euro 2016 qualifying campaign off to an ideal start in Budapest.
After disappointing performances in the World Cup qualifiers - including a red card in the 4-2 defeat to Portugal last year - Lafferty felt he had a point to prove against Hungary.
"I think in the last campaign I let myself down, more importantly I let the manager [Michael O'Neill] down, and the squad and the fans," he said.
"I knew that my work-rate will always be 110 per cent and hopefully my ability will take me further. Thankfully we did it and I've got the winning goal so I'm happy.
"Obviously I had a lot to prove, there were a lot of people talking about how much I want to play for my country, saying I only give 50 per cent but I think that's rubbish. Anyone who knows me knows I'm always up for selection.
"Everybody makes mistakes, every single person, and I'm no different but we had a point to prove and we did and we took our rewards with the goals."
Lafferty's winner was a scrappy affair, as the forward scrambled the ball over the line under the close attentions of a covering defender, but the 26-year-old was unsurprisingly keen to claim the goal as his own.
"A few of the lads were telling me it was an own goal but I got the end touch, definitely," he said.
"I had two or three chances at it. If it was an own goal it was an own goal but I definitely got the final touch."
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