Princess Diana's niece said it was "overwhelming" to be thrust into the spotlight on the day of the Prince Harry and Meghan Markle's wedding.
Lady Kitty Spencer said she thought she picked up someone else's phone by accident after gaining hundreds of thousands of Instagram followers on the day of the wedding of the Duke and Duchess of Sussex.
The model, who is Harry's cousin and the daughter of Diana, Princess of Wales's brother Earl Spencer, called it "overwhelming."
Her Instagram follower count jumped from 37,000 to 500,000 overnight and she told Town & Country magazine: "I woke up the next day and looked at my phone and thought, 'Whoops, did I take someone else's by mistake?'
"It was very weird, and a little bit overwhelming."
Lady Kitty attended the wedding with her siblings, and said she has particularly missed her sisters during lockdown, while they have been in South Africa.
She said: "We are a bit of a tripod. It's been horrible to be separated this year.
"They are in South Africa, which is only an hour ahead, and with two flights going there a day, you usually have the comforting thought of 'I could always be there in the morning if I needed to be'.
"It's been awful to be completely shut off, and thinking, come what may, we can't be there for each other..."
Lady Kitty added she is adamant that she will always keep her own love life private, telling the magazine: "It's not that I don't place an importance on love.
"It's because, for me, love is the most important thing in the world, and I will protect it with all my heart by not making it a topic of discussion.
"You open yourself up to other people having opinions, and it just isn't relevant to anybody's life but mine and my family's."
Lady Kitty was born in England and raised in South Africa but spent much of her childhood at Althorp, where Diana also grew up, and which will be inherited by her younger brother Louis.
She said: "Primogeniture can be a tricky topic, because as times are changing, attitudes are as well.
"We've grown up understanding that it's Louis to inherit, and Louis will do an incredible job."
The summer issue of Town & Country is on sale from May 13.
