Britney Spears' First Day at X Factor: Did She Really Leave Early?

Get all of the inside scoop on how the pop princess and Demi Lovato did during audition in Austin

All hail, Britney Spears!

The pop princess was welcomed by the roar of about 4,000 people who crowded into the Frank Erwin center for her debut as an X Factor judge.

So how did she do—and why was she missing from the last four tryouts? Read on for the full scoop from inside the arena...

Spears' first X Factor comment from the judging panel? The 30-year-old told a teen boy he could be bigger than Justin Bieber!

The "Womanizer" singer remained sweet and calm, only giving two no's during the auditions. Her harshest critique for one poor chap who had no chance of getting through was, "I feel like you need a new teacher to teach you how to sing."

Other than that, she found something nice to say to ever hopeful. "Texas has a lot of talent - seriously!" she tweeted. "Loving @TheXFactorUSA auditions so far."

Spears sat in the seat once filled by Paula Abdul with Demi Lovato taking the place of Nicole Scherzinger.

Lovato proved to be fun and feisty, often taking jabs at Simon Cowell and his age. She even went so far as to call him, "grandpa." "OMG!!! This is so much fun! #XfactorUSA," she tweeted.

About 14 soloists and groups sang for the judges. The X Factor peeps have asked us not to spoil the upcoming season by reporting who did and didn't make it to the next round.

After the tenth contestant, Spears was escorted backstage—and she didn't come back for the last four hopefuls.

We're being told she wanted to take a break.

None of the other judges mentioned her sudden departure—even when some in the crowd shouted, "Where's Britney?!"

And a needed break is all it was.

Spears was back for the second show taping—and stayed for the entire three-hour shoot. And the really good news? She seemed to have loosened up a bit.

Spears and Lovato chatted a lot more than they had earlier in the day. The two stood up at their chairs and danced together during a performance by a hip-hop trio. When all four judges agreed that one rapper was one of the worst auditions of the day, Britney smiled and offered, "I like your hat."

And when Cowell was especially mean to one contestant, Spears sneered, "That was rude, Simon!"

But even she got booed by the audience when they didn't agree with one of her critiques. L.A. Reid playfully announced they can't boo Ms. Spears. Lovato and Cowell continued to tease each other.

The "Skyscraper" singer flirted with the young male contestants, telling one with a Southern accent, "I love a country boy."

The judges will return to the same arena tomorrow for two more audition show tapings.