Prince's Secret Health Struggle: Everything We Know About the Circumstances Surrounding His Mysterious Death

Prince didn't want the world to know he was in pain.

When the 57-year-old singer took the stage in Atlanta Apr. 14, he apologized to fans for canceling two concerts the week prior—unaware that the performance would ultimately be his last. "I was a little under the weather," Prince said. "But we're here now, and I'm going to take this time to thank each and every one of you for coming out and enjoying this time with us." Perhaps presciently, Prince also told the audience of about 200 fans, "Wait a few days before you waste any prayers."

As one concertgoer recalled to NBC News Friday, Prince also thanked his doctor multiple times on stage. "The doctor was standing on the stage next to him and he wanted everybody to give an applause for that. Then about five seconds later he said, 'Let's give another applause for him.' It was kind of weird because the doctor he didn't even put his hand up or anything; he just kind of stood there. So, it was a little awkward in that moment," Patricia Chavez said. "I didn't really realize it, didn't think anything, but maybe he was a little bit more sick than he gave off."

After the show, Prince's private plane made an emergency landing in Moline, Ill. His rep claimed that the "Purple Rain" singer was battling a prolonged case of the flu, but a source with direct knowledge of the events told NBC News that the jet was diverted because an "unresponsive male" needed immediate medical attention; Executive Jet Management had "no comment" regarding that particular flight, the passengers, or any flight that it operates. Airport police contacted the Moline Fire Department for EMS service Saturday, and Prince was rushed to the hospital. Just before noon, though, his plane was back in the air and en route to Minneapolis.

"There was some concern from those in his circle about his appearance and something changed with his energy," a source close to Prince tells E! News exclusively. "Prince was very energetic and lively, on stage and in general, but the past few months or year he hadn't been himself. He seemed off and his energy level was down." Another insider says some people feared "he was going to die" after the incident, so he hosted people at Paisley Park later that night to convince them he was OK. "He wanted to have the party so people knew he was still alive."

The public didn't question it further. But it became increasingly hard for Prince to hide his issues from his inner circle. According to one of his friends and collaborators, "A week or so ago he started not feeling well and expressed that to a few close friends. He never spoke about what the illness was, only that he was fighting a cold and he will get better and not to worry. He never liked to complain." Prince was recently supposed to go out to dinner with friends, but he canceled at the last minute. "He said he was still not feeling well and he needed to reschedule."

"He had not looked well for the last year," someone who's known Prince for 30 years tells E! News. "People were worried about him." According to another source, "He had a very bad hip and needed a hip replacement but wouldn't get it fixed." Because he was a Jehovah Witness and believed in bloodless treatments, the source said he "couldn't have a blood transfusion" needed during surgery. To cope with his discomfort, multiple sources confirm to E! News that Prince had been taking Percocet, a narcotic that can treat moderate to moderately severe pain.

An autopsy was completed Friday at 12 p.m. ET and it will help determine what caused Prince's death; results are pending. Prince's body has since been released to his family. Though TMZ reported that Prince had been hospitalized for a drug overdose less than a week before his death, those close to him refuse to believe he would ever abuse hard drugs. "He was too much of a perfectionist, too much of a workaholic. He wouldn't have derailed that," his friend of 30 years tells E! News. "The announcement of his autobiography, his music—he would never let anything get in the way of that. He wouldn't have ruined it." As his friend L.A. Reid said on Today, "The thing that really bothers me about it is the Prince I knew was super healthy, vegan, wasn't an abuser of drugs, wasn't an abuser of alcohol.

Reid said what many are thinking: "The whole thing is really mysterious to me."

—Reporting by Sara Kitnick

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