She canceled a number of promotional interviews with the press last week but managed to get back in shape for Sunday's concert.
Ke$ha's performance at a London pop concert on Sunday, June 6 was thrown into jeopardy after the singer fell sick with a throat infection. The "TiK ToK" hitmaker axed several promotional interviews in the U.K. on Friday while suffering from a sore throat, and made an emergency appointment at a Harley Street clinic.
It was feared Ke$ha would have to pull out of her slot at the Summertime Ball gig on Sunday but the singer played through the pain for fans at the Wembley Stadium show. A source tells Britain's Daily Mirror newspaper, "We knew she was back to her old self when she started shouting 'F**k!' to the crowd."
Ke$ha is due to be back to Canada soon for she has been booked as a performer at MuchMusic Awards on June 20.