On Monday, the star shared an amazing throwback picture from the 1990s, and she looked completely unrecognisable.
In the close-up shot, the Hollaback Girl singer was looking incredibly baby-faced while wearing a red polo shirt.
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Gwen also had an assortment of heart rings, a bindi, some dark lipstick, and some partially painted nails.
And instead of her platinum blonde hair that fans from today might be accustomed to, she had a much darker colour.
She referenced her youthful appearance in the picture's caption by using a baby emoji. She also wrote "time" alongside a plane emoji, hinting at the expression 'time flies'.
Fans couldn't believe their eyes with the photo, as one said: "Babe!" and another quickly added: "YOU'RE SO BEAUTIFUL!"
The star looked unrecognisable
A third commenter praised the singer's eternal youthfulness, writing: "Time is not better than you," while a fourth commented: "Alright, baby queen. We see you."
One hopeful fan hoped that Gwen's post could be a hint towards something, as they wrote: "Ohhhhh, what's this mean?"
Although the former No Doubt singer didn't confirm whether her post was a hint towards anything, it will be the 25th anniversary of the release of Don't Speak later this month, which centred around her break-up with her bandmate Tony Kanal.
The singer didn't have her platinum blonde hair in the throwback
The popular song was number one for 16 non-consecutive weeks, a record for the time, and was the most widely played song on radio stations in 1996.
Gwen's incredible ensemble consisted of a sparkly crop top with an equally sparkly jacket thrown over it.
She also wore some ripped jeans, with threads and chains covering the tears and some fishnet nights emblazoned with 'Slow Clap'.
Her band rocked similar looks, with many wearing fishnets with plaid skirts and crop tops.
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