Allison Janney had already nabbed a SAG Award, a Golden Globe, and a Critics鈥 Choice Award for her turn as Tonya Harding鈥檚 estranged mother in I, Tonya, when she took the stage to accept the BAFTA for Best Actress in a Supporting Role at Sunday鈥檚 awards ceremony in London. But even then, she quickly learned that you really can鈥檛 win 鈥檈m all. During a hilarious exchange on ABC鈥檚 Jimmy Kimmel Live!two days later, the Mom star shared a story about her 鈥渁wkward鈥 meeting with Kate Middleton and Prince William at the event.

Fresh off her win, Janney decided to kick off her heels at Royal Albert Hall 鈥 and then she learned that the Duke and Duchess of Cambridge wished to greet all the victors. 鈥淚 realized when they started going around that I had taken my shoes off,鈥 she recalled. 鈥淪o I was about to meet the royal couple Fred Flintstone-style, in my bare feet!鈥

Standing eye-to-eye with the pregnant mother-of-two, who鈥檚 expecting her third child in April, the six-feet-tall 鈥 and 鈥渧ery nervous鈥 鈥 Janney noted their similar heights, to which the royal replied that she had on 鈥榲ery high heels.鈥 The seven-time Emmy winner鈥檚 response? 鈥淚 said, 鈥楬oney, you need to take those shoes off 鈥 your highness honey.鈥 I called her honey,鈥 she told Kimmel.

But Janney said that the 36-year-old Duchess wasn鈥檛 fazed. 鈥淪he smiled, I鈥檓 sure it was fine,鈥 added the actress. 鈥淏ut to me it was, 鈥楻eally? I鈥檓 such a rube.'鈥

Appearing on CBS鈥 The Late Late Show with James Cordenon Wednesday, Janney continued her gush fest over the royal couple. 鈥淪he was lovely,鈥 she said of Kate, admitting she felt 鈥渓ike a bit of a wimp鈥 standing barefoot next to a pregnant woman in heels. 鈥淭hey loved I, Tonya, and it was a pretty cool thing to meet them.鈥

Still, Janney said that there was one person who didn鈥檛 take the 鈥渁wkward鈥 encounter in stride. 鈥淢y mother was very upset with me,鈥 she told Corden. 鈥淪he鈥檚 very all about manners and etiquette. She just called my assistant and said, 鈥榃hy can鈥檛 you have someone give her a pair of ballet slippers? Why can鈥檛 you have another pair of shoes?'鈥

Maybe Janney will take the note on carrying flats for March 4鈥s Academy Awards, where she鈥檚 up for the Best Supporting Actress golden statuette.

(photos via Randy Holmes/ABC + Jeff Spicer/Getty Images)