Selena Gomez All Smiles Rocking Matching Pajamas With Her Gal Pals -- See the Pics!

The 'Wolves' singer also enjoyed hot Pilates class with her close friends on Monday.

Selena Gomez is rockin' a permanent smile!

Amid speculation that The Weeknd's six-song EP, My Dear Melancholy, was written about the 25-year-old "Wolves" singer, Gomez has been looking happier than ever in her latest social media pics. On Monday, she appeared to be in great spirits, spending the day and night with some of her gal pals.

Gomez kicked off the day at Hot Pilates in Los Angeles with her "Monday squaaaad," Shannon Nadj and Theresa Marie Mingus. 

The former Disney star sported a white T-shirt with black shorts and matching sneakers, while her friends donned variations of black-and-white fitness gear.

After their sweat sesh, they ventured around town, belting out songs from The Lion King soundtrack, which was documented on Mingus' Instagram Stories.

Instagram Stories

The night ended with Gomez and Mingus attending "a pajama jam" with Paigey Reed and Rebeka Walters. The girls were all adorably dressed in matching pink PJ sets, which Gomez styled with knee-high socks.

Nights in with your BFFs = the best kind of parties!

As ET previously reported, ever since The Weeknd dropped his surprise EP last week, the Internet has been buzzing over the first track, "Call Out My Name," in which he croons, "I almost cut a piece of myself for your life/ Guess I was just another pit stop/ Til you made up your mind/ You just wasted my time."

Some suggested that the lyrics make a direct reference to Gomez's kidney transplant -- which occurred a few months before the couple broke up -- as well as Gomez rekindling her relationship with Justin Bieber soon after she and The Weeknd, 28, called it quits last October.

A source tells ET, however, that Gomez never would have asked her ex-boyfriend to be her kidney donor.

"It's just a lyric and he knew it would strum up attention and that people would interpret it exactly as they have, but he was never actually going to donate his kidney to Selena," the source claims. "Sure, he was her boyfriend at the time, so it perhaps crossed his mind to get tested to see if he was a match -- which is incredibly rare -- but it never got anywhere close to actually happening."

Hear more in the video below!

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