Selena Gomez parties hard at Britney Spears' Las Vegas show. She also hit the after-party.

Selena Gomez parties hard at Britney Spears’ Las Vegas show. She also hit the after-party.

Selena Gomez partied hard in Las Vegas along with other celebrities to mark the premiere of Britney Spears new residency at the Planet Hollywood Casino, showing no signs of “Lupus,” or claimed tour-canceling “exhaustion.”

Gomez, 21, shocked fans in Australia, Japan and Southeast Asia by canceling 11 tour stops in Japan, Shanghai, China, Kuala Lumpur, Malaysia, Manila and Australia.

The only reason cited by her management was that Selena was suffering from “exhaustion” and needed time to spend on herself. The venues were left on the hook for potentially millions of dollars in lost sales.

Gomez’s “Stars Dance Tour” could be forced to cover the losses, if her insurance company refuses to pay damages because of a breach by the star of her contracts to perform, TheImproper reported exclusively Dec. 21.

Selena Gomez Parties Hard in Vegas
(Click Photos to Enlarge!)

Within days of the cancellation, some gossip sites reported without confirmation or evidence that Gomez may be suffering from Lupus, an autoimmune disease that causes extreme fatigue, headaches, painful or swollen joints and fever, according to the Lupus Foundation of America.

In all her years of performing–she was a Disney teen star–Gomez has never mentioned the affliction, although the disease is believed to have genetic origins with onsets as early as 15. In 2010, Lady Gaga revealed that she tested “borderline positive” for lupus.

Gpmez’s management declined to comment on the report.

Other unsubstantiated, and apparently untrue reports in sketchy gossip sites like HollywoodLife claimed Selena was pining for ex-boyfriend Justin Bieber, even though Bieber acknowledged in a radio interview that they weren’t speaking to each other.

Whatever Gomez’s alleged ailments, she was the picture of health and energy at Spears’ “Pieces of Me” show. She danced, jumped, shouted and cavorted with other guests without showing any abnormal signs of fatigue. She was captured partying hard in several photos posted on Instagram.

Her behavior deepens the mystery behind the real reason she canceled the Southeast Asian leg of her tour.

The “Come & Get It” looked sophisticated in a long black dress. During the stage show, the young star was forced to tie her hair back as she sang and danced along to the music, according to several reports. She spent the whole time on her feet.

She also appeared at the after-party at Vegas adjunct of Hollywood club Beacher’s Madhouse, hosted by Miley Cyrus.

Selena later posted a photo of herself with singer Sia on Instagram with the caption: ‘Sia!! Thank you soooo much for taking me to Britney!!!! Ahhhh.’

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