ET caught up with the 32-year-old Dancing With the Stars pro at the grand opening of Gleb Savchenko and Elena Samodanova's new dance studio, Pro Dance LA, last Friday, where he revealed there was one moment where he thought the surprise would be ruined.
"[The ring] was in my book bag. The only time where I felt like, 'Oh man, the plan could get busted,' was at security check," Chmerkovskiy, who popped the question while the two were vacationing in Venice, Italy, told ET's Lauren Zima. "Both our bags got pulled to the side."
"They went through her bag, and then they got to my bag and I’m like [freaking out]," he continued. "And they’re like, 'You can't travel with this water.' And I’m like, 'OK, cool. Cool. Cool.' I got some of the ice in the other bag."
Johnson confessed that ahead of their romantic getaway, she was thinking a proposal could maybe happen. She said she even searched through her now-fiance's travel bags to see if she could find any bling, but didn't have much luck.
"Then I prepared myself," the 24-year-old dancer said. "I'm like, 'It's not happening.'"
"I was really rude. I was super rude," she added, laughing. "I'm not going to say I went through his things, but I went through his things and didn't see anything, so then I was even more rude."
The lovebirds revealed last month via social media that the two were engaged, with adorable photos from the moment Chmerkovskiy asked Johnson for her hand in marriage. "I knew the moment I met you, you were the man of my dreams and I wanted to be with you forever," Johnson gushed at the time. "Thank you for making my fairytale come true today! Cannot believe I get to call you my FIANCÉ!!!!"