Allison Williams Says 'Everything Is Unrecognizable to Me Now' After Becoming a Mom

Slaven Vlasic/Getty Allison Williams

Motherhood has completely altered Allison Williams' outlook on life.

During a Thursday appearance on the Today show ahead of the premiere her new film M3GAN, the 34-year-old actress discussed her "adorable" baby son Arlo, whom she welcomed with fiancé Alexander Dreymon in late 2021.

"I'm very proud," Williams said. "I get, like, weird and shy when I talk about it, because it's so new. But I'm obsessed with him; it's all I think about."

After Savannah Guthrie — herself a mom of two — noted how "motherhood changes everything," the Girls alum agreed, "Literally everything."

"I had some friends who were like, 'Most of the things stayed the same, a couple of things about my routine shifted.' And as it was happening, I was like, 'Everything is unrecognizable to me now. It's all different,' " Williams continued. "I don't know how people do it any other way."

"It changed everything," she added during Today's fourth hour, with Hoda Kotb and Jenna Bush Hager. "It's just the most unbelievable adventure. I feel lucky every day."

She went on to joke that she's unsure what she used to do with her days before becoming a mom. "What did we do with this time? I think about this all the time," she said. "Just my inbox, just languishing, as if I was just going to get to it.

"The amount of stuff I can get done in 30 minutes is just unbelievable," she noted, praising the organization ability of moms everywhere.

Later on Thursdsay, on Live with Kelly and Ryan, the actress also discussed her baby boy's recent second Christmas, joking to guest host Déjà Vu, "He's really little still, so I'm still off the hook!"

"[He had] no expectations, didn't understand what was going on," Williams added. "I really enjoyed having another year of not having to bring it. By next year, I have a feeling we'll have to really show up."

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Slaven Vlasic/Getty Allison Williams and Alexander Dreymon

RELATED: Allison Williams Makes First Public Appearance Since News She Welcomed Baby Boy

Elsewhere on Today, Williams said she had "lots to celebrate" after Guthrie congratulated her on her and Dreymon's engagement.

Last month, Williams made her red-carpet debut with Dreymon at the Los Angeles premiere of her new horror comedy M3GAN. They also stepped out together for a special screening of the film in New York City on Wednesday.

In an Instagram post documenting the couple's December night out, The Last Kingdom actor, 39, said he was "so proud of my gorgeous fiancée," confirming they are actually engaged.

Dreymon wrote alongside photos from the event, "Premiere of M3GAN with a screaming, laughing, cheering crowd. It's the ultimate fun scarefest."

"I'm so proud of my gorgeous fiancée @aw," he added. "Congratulations to everyone who worked so hard on what will likely be a new cult hit."

RELATED VIDEO: Allison Williams and Alexander Dreymon Make First Red-Carpet Appearance After 3 Years Dating

Back in April, multiple sources confirmed to PEOPLE that the pair welcomed a baby boy named Arlo the previous winter. The trio was recently spotted on vacation with their family, including her father, newsman Brian Williams, at a private resort in Abaco in the Bahamas. Allison was also wearing what appeared to be an engagement ring.

"They seemed to be very happy and very much in love," said a source.

According to the insider, the two initially met while filming the 2020 thriller Horizon Line but have been together since the end of 2019.

"They are both private people individually, and they made the decision to keep this happy news to just a small circle of family and friends," the source added. "But they're over the moon."