Arlen beamed as she explained the coincidental symmetry of her song choice, sharing, "I danced to her song '22' when I turned 22 on my last birthday, so I danced to her yesterday for this birthday."
ET's Cameron Mathison caught up with Arlen and Chmerkovskiy after the show, and the inspirational contestant opened up about the epic surprise.
"That was insane! That was really cool," Arlen marveled. "I don't think cool is a cool enough word for it."
Even Chmerkovskiy, who's danced with some big stars and has some high-profile friends, said he's never gotten a gift like that.
"I felt special for her," he shared, adding, "I was like, 'Damn! That means Taylor saw me, too!"