Ever since becoming the first size-22 model to sign with a major agency back in January, Tess Holliday's life has been a whirlwind – but she doesn't mind one bit.
"My phone still hasn't stopped ringing," Holliday, 29, tells PEOPLE. "It's good, but it's a lot!"
The 5'5" model has already landed major campaigns with Benefit Cosmetics and Torrid, but her career is just getting started.
"I just got back from London three weeks ago," she says. "I'm going to New York this week, then next week I'm going to Montreal and New York again. Then I go to Seattle, New Orleans and Vegas after that, all for work!"
Success has been a long time coming for Holliday, who first tried to get into plus-size modeling more than 14 years ago.
"Nobody was interested," she says of her first open casting when she was 15. "I got one call back and they said, 'Look, you have a pretty face, but you're too short and you're too big.' "
"I was getting shoved into lockers, I was being called names," she says. "I was getting death threats at my house. It was awful."
Despite all the adversity she faced, Holliday never gave up on her dreams to make it as a model.
"I just knew that I could do it," she says. "I wasn't the best, and I still am not the best. They key to it is just doing it."
For more of our interview with Holliday, pick up the latest issue of PEOPLE, on newsstands Friday