NEW YORK CITY, NEW YORK: Madonna's friends fear that the 'Queen of Pop' has been overworking herself to outperform younger artists such as Pink and Taylor Swift. This comes after the 64-year-old was put in intensive care after a serious bacterial infection.

Madonna who was scheduled to begin a six-month global 'Celebration' tour on July 15, is currently 'feeling better' and recovering at her New York residence with her children by her side. However, Madonna's pals claimed, “She was working overtime, but she clearly burnt herself out and people around her have been politely reminding her that she is not 45 any more, let alone 25," as per the Sun.

What happened to Madonna?

Worried friends of Madonna have disclosed that in order to keep up on the path with fresh talent like Taylor, she "burnt herself out." An unnamed source stated, "The countdown was well and truly on. Madonna had all her chips on one number, which was this tour." The insider further added, "She needed to pace herself. Pushing herself so hard was extremely risky." They said, "But if she can get herself back in shape, the tour will have a whole lot more buzz around it, and she’s already got loads of publicity — even if it’s the wrong kind. Madonna is in it to win it and working harder than anybody."

'There were concerns about another Michael Jackson situation'

Another friend worried that she could have suffered like Michael Jackson, who died in the days before his 'This Is It' tour in 2009. "Madonna was in good spirits before the incident, but some friends had encouraged her to take it easy and find time for rest because of the grueling schedule she had ahead of her," an insider stated. "Many of us feel the constant remarks about her age have put pressure on her to compete, so we are relieved that she has been forced to take time out and put her health first. People were really worried about her." The source went on and said, "Nobody would say it out loud but there were concerns about another Michael Jackson situation if she doesn’t slow down a bit."

How is Madonna's health now?

Despite the health concern, the 'A League of Their Own' singer has no intention of curtailing her 'Celebration' tour when it is rescheduled. "She is home, happy and taking meetings, and she has rejected a proposal to scale back on the tour as she still wants to deliver as many dates as possible when she’s regained her strength," the source added. "Her condition is completely curable and she’s working with a group of doctors to boost her immune system. She’ll be back, I am 100% sure of it. God bless her. I hope she is still working and still killing it at 100."