Encouraged by her father, Flagg became interested in writing and performing at an early age, writing her first stage play when she was only 10 years old. As a teen, she entered the Miss Alabama pageant, where she won a scholarship to a local acting school for one year. After that, Flagg began co-hosting a locally produced "Morning Show" on WBRC-TV in Birmingham, but when she was denied a raise, she quit her job and decided to move to New York City.