Has Stardom Become Too Much for Justin Bieber?

Justin Bieber
After hearing about Justin Bieber's erratic behavior lately, including cancelling his concerts (and even showing up two hours late to one), you've got to wonder if he's on drugs. He just cancelled another concert in Portugal after having a troubled European tour, according to NY Daily News.

Some have suggested that Selena Gomez dissed Bieber with the recent release of 'Everybody Knows.'

Perez Hilton said. "Thankfully it isn’t because of his health, however, it’s rumored that the cancellations were due to low ticket sales."

What do you think?