King Charles Is 'Moved' by Public Support After Queen's Death: He 'Expects to Be the One Who Disappoints'

Now the work begins for King Charles III.

As retreats from the frenetic public-facing role of the last two weeks at his Scottish home, Birkhall, the public has seen plenty of evidence of the man who is now King. His character — flaws and all — have been on display, but he has largely come through it with the backing of the British people, a biographer says.

"It's been interesting because he's been clearly buoyed and moved by the public support for him," says Catherine Mayer, whose book Charles: The Heart of a King has been recently updated. "I know him well enough to know he'd be surprised by that. He always expects to be the one who disappoints. But the excitement has lifted him."

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There have been, as Mayer puts it, "signs of dissent" on some outings, and she assesses that his character has divided people at times. The incidents with pens — at both his Accession declaration, when he was tetchily bothered by an ink well in front of him, and then when signing the visitors' book in Northern Ireland — "divided interestingly along demographic lines but not what you'd expect," Mayer says.

"It was the young who liked his pen incident, as they saw that as humanizing and authentic," she says. "Yet the older people were complaining because it wasn't what the Queen would have done."

Mayer says the King's irritability amid extreme stress displayed on those occasion was very much in character. "He's a very engaging and funny and warm but absolute peevish when things don't go his way. We got glimpses of that," she tells PEOPLE.

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"He has struggled his whole life to subdue his emotions. He's an emotional person but is stuck in a role that puts him on show. He always sublimates his emotions to the spectacle," she adds. "The week showed he's quite good at doing a straight face, but you can see the emotions tracing themselves across his face. And that's a humanizing thing."

"And there have been times he's been on the edge of laughter as he and [Queen Camilla] are terrible gigglers," she says. "You've seen from his least attractive quantity, which is his peevishness, to his sorrow for his mother to his sense of humor beginning to break through."

BBC America King Charles III

Just like his mother before him, the daily papers of state have been arriving for King Charles in red boxes to his home on the Balmoral estate in the Scottish Highlands. He's been absorbing them, and, no doubt, planning the days and weeks ahead as leader of the monarchy that he took over upon his mother's death. Of course, Charles had to wait to 73 to "do this thing that he's been told his whole life that's what he's on the earth to do," as Mayer says.

In that, he has had the best training, funeral guest Ralph Goodale says. Goodale, Canadian High Commissioner in London, says the preparation will stand him in good stead.

"He has had the longest apprenticeship for this role. And he's had the most amazing role model and remarkable teacher in his mother to get ready," Goodale tells PEOPLE. "Still, at a human level it must be one of the most difficult weeks of his life."

DANIEL LEAL/POOL/AFP via Getty Images King Charles and Prince William

He adds of the rest of the royal family in Westminster Abbey during Monday's state funeral, "You could see in some of the stoic looks on the faces of the family that the reality of having lost this wonderful person is beginning to sink in a bit."

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"This was the final farewell. All the ceremonies and parades and services — had been leading up to the Abbey. And that was sinking in for a lot of people. There was intense sadness because of that," he adds. "Also in the air there was a sense of gratitude and celebration for all of the joy and all of the good that Queen Elizabeth II represented. That photograph with that beaming smile that the palace released was a message that this is the way they want us all to remember — with that big grin and sparkling eyes."