The New Zealander headed the Dons in front after four minutes and added a sublime second on the volley. He said the second strike was one of the best of his career after two bicycle kicks, and comparable to his goal against Bahrain in November 2009 which took New Zealand to the 2010 World Cup, their first qualification since 1982.
"The New Zealand goal was a big one," said Fallon. "If that goal can lead us on to silverware that will be up there with my greats."
He added: "We've got a great opportunity. We've put ourselves in a great position to try to get something. We've been doing well and grinding out results and hopefully we can do well in the semi.
"The way we're playing we can take on anyone. We proved we could foot it with Celtic, so whether we got Celtic in the semi or the final, it doesn't really matter to us. We feel we can beat anyone on our day."
There was a touch of fortune about Fallon's opener after Scott Vernon kicked the ball out, yet the Dons were awarded a corner.
The incident infuriated Motherwell boss Stuart McCall, who was at half-time sent to the stand by referee Craig Thomson.
"Everyone makes mistakes," said McCall, who believes he was punished for telling Thomson and his assistant the decision was "embarrassing".
McCall could face further censure from the Scottish Football Association for the incident.
"I thought Craig, once the ball came in, would make it right," McCall added. "But as Craig says you can't just make up fouls, but it happens week in, week out, you watch it on telly. I felt a sense of injustice, but I could tell it affected the players for 10 or 15 minutes. I'm hugely disappointed that they stopped me doing my job in the second half."
Source: PA
Source: PA