In just four years, Justin Bieber has gone from fielding innocuous questions about his haircut to denying that he's in desperate need of rehab. Bieber has grown up and gone into tabloid territory, with his recent troubles making some question whether he's just the latest teen star gone wild.
In what could have been his worst week ever, the 19-year-old struggled with his breathing and fainted backstage at a London show, was taken to a hospital and then was caught on camera clashing with a paparazzo. Days earlier, he was booed by his beloved fans when he showed up late to a concert.
Those incidents come after photos of Bieber appearing to smoke marijuana hit the internet, and some headlines have suggested that he is going through a Britney Spears-style meltdown.
Others suggest he's struggling with a more common condition: being a teenager.
Donnie Wahlberg, who was just 14 when New Kids on the Block debuted on the music scene in the late 1980s, said he remembers the pressure and hard times that came with being a teen celebrity.
"Justin Bieber's making mistakes that everyone makes and he's probably trying things and exploring things that most kids his age explore, but the problem is he's got 50 paparazzi chasing him around when he does it," Wahlberg (43) said.
"When we are 19 and 20, we think we can take on the world and we forget that there is a lot of life left to live in front of us. Hopefully he'll get through and find his way into a long career and a healthy adulthood."
Pressure was evident in the days following his collapse backstage at the London O2 Arena, as the Grammy-nominated singer wrote on Instagram that he's sick of the "countless lies in the press" and that he would not be heading to rehab.
"I've accomplished more than I could've ever dreamed of, I'm 19 and it must be scary to some people to think that this is just the beginning," he wrote.
"I'm a good person with a big heart. ... All this isn't easy. I get angry sometimes. I'm human. I'm gonna make mistakes."
Even mistakes seem like new territory for Bieber: since breaking out at 15, he has seen five albums hit No1 on Billboard's 200 albums chart and nearly 20 songs crack the Top 40. He's had several world tours, launched a massively successful 3D movie about his life and made deals that include his own dolls, nail polish and fragrances.
He's got a social media presence that includes 52 million likes on Facebook and 36 million Twitter followers.
But does that leave any time to be a kid?
Nick Carter, considered the wildest of the Backstreet Boys, was also the group's youngest member when they began to dominate the charts in the 1990s.
He recalls the days when he grew mad as an overworked teen who yearned for a normal life: "I remember getting tired. I remember getting burned out and I'm like, 'Let me relax' and you have managers, and the record label ... and then before you know it, the artist gets resentful and starts to revolt and that's when you end up with a situation like what's going on," he said.
"In a lot of ways, you're resentful and you're missing out with your friends, your childhood, you see all of your high school friends growing up ... and you're like, 'Oh, I got to go back on tour'."
Vincent Herbert, who signed Lady Gaga and also discovered the teen R&B boy band Mindless Behavior and singer JoJo at 12, said that young singers need role models and that there must be "time for music and time to be kids".
"I think sometimes young artists get to that point because they're young and it's a lot and it gets overwhelming.
"I don't think Justin Bieber is at that moment, I just think he had a bad week."
But he acknowledges that, for young artists, the pressure sometimes leads to meltdowns: "No one's a machine – we're all human."
Britney Spears became the poster child for that after she shaved her head and lost custody of her children.
Carter said his bad attitude began to affect his business, and young singers must think twice about their actions even when they're at a breaking point.
"I probably messed up a particular movie I was going on an audition for because I showed up late and people looked at me like I was disrespecting them when really I was just out of my head," he said.
"For years I've been scrounging and clawing and proving through my work and staying away from alcohol and trying to be the best person I can be to make up for all the things I've done."
While Bieber, who was raised by a single mother in Canada, has held on to a pretty squeaky image, last year began to suggest some troubles.
He vomited twice onstage during a concert in Arizona, he was cited for speeding on a LA freeway and LA County Sheriff's investigators questioned the singer after he reportedly scuffled with paparazzi who tried to photograph him and then-girlfriend Selena Gomez.
"What he's going through is just the passage of adulthood and to go through that with this kind of scrutiny – it's hard," said Bill Werde, the editorial director of Billboard.
Both Carter and Wahlberg are reluctant to give advice simply because, when they were in his position, they wouldn't have listened.
"The facts are that he's going to do what he wants to do," Carter said. "What happened to me when I was that age was the same thing: it's power. Your parents are telling you, 'Please don't do this, please don't do that' and you're looking at them going, 'Who are you? I am me'."