Actress Dame Imelda Staunton has said she “absolutely adored” portraying the late Queen Elizabeth II as she received her royal title at Windsor Castle.

The 68-year-old, who earned Bafta TV and Golden Globe nominations for the role in Netflix’s hit drama The Crown, was honoured for her services to drama and charity by the Prince of Wales on Tuesday.

She is widely known for playing the evil Dolores Umbridge in the Harry Potter films, with her other film credits also including Downton Abbey, Paddington and Nanny McPhee.

Asked if it felt surreal to be recognised with her damehood by Charles in the King’s Birthday Honours having played his mother, Dame Imelda told the PA news agency: “They’re two very different worlds and you have to sort of get serious about that and go, ‘We were on the television and this is for real’.

“[William and I] didn’t talk about that, but it was a huge privilege. That was two years of filming, and I absolutely adored it.

“It was of course devastating when Her Majesty died – we were filming as well, it was tricky.”

Dame Imelda starred as the former monarch in the fifth and sixth series of the royal drama, following in the footsteps of Claire Foy and Olivia Colman – who played younger versions of Queen Elizabeth II.

She said she was “inconsolable for quite some time” after the Queen’s death, and that subsequent filming of The Crown was “very strange”.

She defended the series’ depiction of a fictionalised version of historical events, saying: “It’s a drama, not a documentary.”

“They do it with such care. They’re not, they’re not out there to, you know, give a bad press,” she said.

“As a dramatist, you have to imagine what someone was saying behind those closed doors. I think it was a tremendous piece of work and a tremendous tribute to the royal family.”

Dame Imelda has also had a hugely successful stage career, including numerous Laurence Olivier Award nominations and wins in The Beggar’s Opera (1982), Into the Woods (1991) and Sweeney Todd (2011).

Asked what she enjoys about rotating between film, television and theatre, she said: “Getting better, because they each demand different things of you.

“I’m walking in the footsteps of Maggie Smith, Judi Dench, Peggy Ashcroft, all these great actresses, and they’re great actresses because they kept on working and they kept being challenged.

“That’s what I sort of insist to myself that I must do – don’t take the easy journey, make it hard for yourself.”

Dame Imelda’s charity work has included being an ambassador for national homelessness charity Crisis and supporting the international disaster relief charity ShelterBox.

She is also a patron for Breathe Arts Health Research, which helps children with a paralysis condition called hemiplegia with physiotherapy.

Speaking about her work with Crisis, Dame Imelda said: “Who wouldn’t do something for the homeless? The situation, as the Prince of Wales knows, is getting worse, so anything one can do to help there is hopefully useful.”

She added it was “very special” to see William again as he had previously made her a CBE.