"As bad-ass as her image is, she is 200 percent girl," Shelton, 33, tells PEOPLE about Lambert's excited anticipation when it comes to planning their wedding.
Shelton, who on Sunday proposed to Lambert, 26, in the Oklahoma woods, made his first public appearance since their engagement at a No. 1 party in Nashville on Wednesday night for his hit "Hillbilly Bone."
Sporting the diamond and platinum sparkler Shelton picked out for her, Lambert looked on from the wings, clutching her Chihuahua pup, Cher.
Cher was Lambert's "good luck charm" – at her side when Shelton popped the question and when Lambert scooped up three ACM Awards last month.
"Being engaged ups the excitement level for us another notch," Shelton says. After nearly five years of dating, "it was time" to move to the next step. "I think everybody around us probably saw it coming."
Lambert, a self-professed addict of wedding reality shows like Say Yes to the Dress and Whose Wedding Is It Anyway?, tells PEOPLE she's eager to begin her dress hunt. "I don't think I can talk myself out at least one trip to [New York's] Klenfeld's Bridal!" she admits.