The Irishman, one of Hull’s outstanding performers following his switch from Sheffield United last August, was told by supporters invading the KC pitch at the final whistle that the Hornets were drawing 1-1 with Leeds United.
Quinn believed that meant Watford would – providing the score at Vicarage Road stayed the same – claim second place behind champions Cardiff.
He explained: “The supporters ran on at the end telling me that Watford and Leeds were drawing 1-1. Even when I came into the tunnel and I was watching it on the TV, I still thought Watford were going to go up with the point they had.
“I didn’t work it out and thought, ‘Watford have got this’. Someone put me right and when Leeds scored it was just ecstasy. It is such a fine line between success and failure in this sport.
“The highs and lows that come along are incredible. I’ve had a few failures in the past in the play-offs so I am mighty glad this has been a success.”
When Quinn joined the Tigers, the terms agreed stipulated the Blades would be paid £2,000 per appearance by the Irish midfielder to a maximum of £100,000.
Hull’s promotion is now understood to have triggered a further six-figure payment to the South Yorkshire club.
He added: “Getting beaten by Burnley (in the 2009 Championship play-off final when still at Bramall Lane) by the odd goal was hard. As was getting relegated from the Premier League (in 2007) with all the (Carlos) Tevez affair, when we should have stayed up.
“Everything I’ve done seems to have gone against me when it has mattered. Even against Cardiff, I thought it was going to happen again when we gave the penalty away.
“It is not supposed to happen like that, but someone was shining down on me.
“My mum (Alice) and dad (John) have passed away, God bless them. So this is one for them. I am sure they were looking down on me.
“I am proper emotional, I just wish they were here for me. My dad would take me to training week-in and week-out. There’s millions of kids trying to be footballers and you get to the Premier League. I just wish they were here to give them a hug and tell them I’ve done it.
“My dad would always tell me to enjoy my football and since he passed away that is all I have done.”