The footage which has captured the world's attention - of volunteer firefighter David Tree feeding Sam water from a bottle - was in fact filmed prior to the deadly bush fires, during a preventative backburning operation in a fire at Delburn the previous week.
Tree says he only took the video to show his daughter and feels overwhelmed by the international interest that has ensued.
"I emailed the photos out to a few people to cheer them up. And it's just snowballed from there," he told Melbourne's Age newspaper.
"It's just gotten so out of control, I definitely wasn't up for it. My head's spinning. I'm having a hard time dealing with it ... Mentally ... it's just, wow. I'm really outside my comfort zone."
Tree, who has since been invited to appear on American chatshows and to give international media interviews, said he never meant to deceive anyone but that he was pleased Sam's story gave people a distraction "amidst all the tragedy".
"I think it happened about a week and a half ago, but you'll have to bear with me - I'm losing track of the days," he told the Age.
"I think people needed a release. I think that's why they've related to the koala so much."
The worldwide affection for Sam was further highlighted yesterday when celebrity gossip site TMZ.com was forced to apologise for poking fun at the cuddly marsupial.
In a post entitled Koala to Firefighter: I Won't Tap That!, TMZ wrote: "After battling some of the worst wildfires ever to hit Australia, a firefighter shared his bottled water with a pampered koala on Monday. Afterwards the new friends went to Pilates and dined on sushi."
Enraged readers posted comments accusing TMZ of insensitivity in the wake of Australia's worst ever bush fires.
"Pampered? The little animal just lost a lot of its habitat, including food and water supply, not to mention all the human lives lost as well," one wrote.
Another commented: "C'mon TMZ it is extremely disgusting to make light of a very serious situation in which many people have lost their lives. This is a very touching picture depicting human compassion. If more people could be like this firefighter the world would be a better place!"
TMZ later issued an apology, saying its comments had been "out of line".
"We officially apologize for poking fun at Sam, the koala rescued from the fires in the Australian wilderness.
"Sam was photographed drinking bottled water and we made a joke....and it was out of line," the apology read.
Tree was reunited with Sam yesterday, after she was bandaged by staff at the Mountain Ash Wildlife Shelter.
"It was great to see her again. She had a sniff and I got a bit up close and personal, and I even got a bit choked up," he told the Age.
"You could see where the black soles of her paws had been burnt off and they were pink and looked sore," he told news.com.au.
"She's been through a lot."