Heidi Klum Says She Panics When Leni Doesn't Answer Phone at College: 'Worrying Is Already Starting'

Heidi Klum/Instagram Heidi Klum (left) and daughter Leni Klum

Heidi Klum is experiencing some jitters about her daughter being on her own in New York City.

During an appearance on The Late Late Show with James Corden on Monday, the America's Got Talent judge said "it's so sad" knowing daughter Leni, 18, is in New York while she's in Los Angeles.

"It's crazy, today she had her first day in college," Klum shared in conversation with Corden and fellow guest, famed photographer David LaChappelle.

"This weekend, she just moved in, and I call her. Normally she picks up, but then three, four hours I don't hear anything. And already, my head is going 'Where is she? What is she doing? Why is she not answering?' Already the worrying is starting."

Speaking of Leni's milestones in recent years, she said, "First they have a car and they drive, and that's hard. Then they move across the country, and that's harder."

Admitting she was calling her "every two hours," Klum joked, "Now I want the number of the roommate, so I can bug the roommate if she doesn't pick up ... And then I'm going to get the number from the neighbor."

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

Last week, Klum — who also shares daughter Lou, 12, and sons Johan, 15, and Henry, 16, with her ex Seal — shared a throwback photo of when she was pregnant with Leni at the Victoria's Secret Fashion Show. The 49-year-old model mused over how fast her daughter is growing up as she felt like the picture was taken "only yesterday."

"Today is your big move to head off to college… 🥹😿Seems like only yesterday that this photo was taken when I was four months pregnant with you safe and sound in my belly. 🤰🏼," she wrote.

"Sometimes I wish I could always have you that close but I know it's now time for you to go spread your wings and fly," Klum continued. "🦋Take flight, be safe and shine bright my @leniklum 💖"

RELATED: Leni Klum Makes Rare Red Carpet Appearance with Dad Seal at Netflix's 'The Harder They Fall' Premiere

Photopix/GC Images Heidi Klum and Leni Klum

In an interview with Entertainment Tonight earlier this month, Klum opened up about the emotions around Leni leaving.

"I am [so proud]," Klum told the outlet. "You know, she has her head screwed on right."

"Right now, college is on top of the list. It's not modeling and she's really excited for that next chapter in her life," she added.

The proud mom said the next chapter means Leni is "unfortunately" moving out.

"Which is obviously sad but at the same time that she's got enough to go for it," she told ET. "She's moving to New York. I started in New York, so she knows New York inside and out because we shot Project Runway there for so many years."