Britney Spears is happily documenting her pregnancy following this week's announcement she's expecting her third child.

The pop star posted a video shared to Instagram on Tuesday in which she calls attention to some of the bodily changes she's experiencing.

"So I have to model my clothes now before I really start showing…," her Instagram caption begins. 

In the beginning of the one-minute clip, Spears rocks her hips from side to side as she wears a floral crop top accessorized with a flower choker, and low-rise gray pants, exposing her midriff.

BRITNEY SPEARS’ EX KEVIN FEDERLINE CONGRATULATES STAR ON HER PREGNANCY WITH SAM ASGHARI

Britney Spears' fiance Sam Asghari

Britney Spears' fiance Sam Asghari said, "Fatherhood is something I have always looked forward to." (Vivien Killilea/Getty Images for GLAAD)

"I had to do the flower n my neck like @sarahjessicaparker … I actually do have a small belly here but at least my pants fit … Well barely!!!" Spears' caption continues.

The video continues to show the "Toxic" singer in a variety of other outfits. One seemed to be an ode to her "Baby One More Time" music video as she wore a white buttoned-down shirt tied above her belly with a black pencil skirt and heels. Another look shows the starlet in a floral black and red mini dress with black combat boots.

"Psss is anyone curious why I’m 4 sizes smaller by the door ???" her caption concludes.

BRITNEY SPEARS SAYS SHE'S 'HAVING A BABY'

The 40-year-old pop star took to Instagram on Monday, sharing an image of a pink teacup and flowers with a lengthy caption.

Britney Spears

Britney Spears appeared to make her pregnancy announcement on Instagram on Monday. (Jordan Strauss/Invision/AP, File)

"I lost so much weight to go on my Maui trip only to gain it back," she began. "I thought ‘Geez … what happened to my stomach ???’ My husband said ‘No you’re food pregnant silly,'" referring to Sam Asghari, 28.

"So I got a pregnancy test … and uhhhhh well … I am having a baby."

The star went on to say, "I obviously won’t be going out as much due to the paps getting their money shot of me like they unfortunately already have … it’s hard because when I was pregnant I had perinatal depression … I have to say it is absolutely horrible."

A TIMELINE OF BRITNEY SPEARS' CONSERVATORSHIP

"Women didn’t talk about it back then … some people considered it dangerous if a woman complained like that with a baby inside her … but now women talk about it everyday … thank Jesus we don’t have to keep that pain a reserved proper secret."

Spears concluded with, "This time I will be doing yoga every day !!! Spreading lots of joy and love."

A rep for Spears didn’t immediately respond to Fox News’ request for comment. 

Britney Spears Sam Asghari

Britney Spears and Sam Asghari got engaged last September. (Kevin Winter/Getty Images)

Her fiancé, Asghari, took to Instagram on Monday to confirm the news, sharing a picture of a family of lions with a caption detailing what fatherhood means to him. 

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"Marriage and kids are a natural part of a strong relationship filled with love and respect. Fatherhood is something i have always looked forward to and i don’t take lightly. It is the most important job i will ever do," he wrote, adding a praying hands emoji.

Meanwhile, some of Spears' fans were confused by her "food pregnant" comment. 

Britney Spears

The singer's conservatorship ended in 2021. (AP Photo/Chris Pizzello)

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Spears shares her two sons, Sean, 16, and Jayden, 15, with her ex-husband, Kevin Federline. 

Federline’s attorney, Mark Vincent Kaplan, told NBC News on Monday, "He wishes her the best for a happy, healthy pregnancy and congratulates her and Sam Asghari as they plan for the excitement of parenthood together."