"I'm on cloud nine," the 23-year-old South Carolina native gushed. "I'm ready to go to Miss America, and I'm really happy to have made history. I'm definitely the first openly gay Miss Missouri, and the first woman to go into the Miss America competition openly gay."
O'Flaherty, who came out to her family and friends when she was 18 years old, said she's excited to be a role model for the LGBT community.
"In the past few days, I've received several messages from other contestants that are out in other states," she explained. "So, that's awesome to hear that maybe I won't need to be the only one going to Miss America this year openly lesbian. That is really exciting."
Although she appears to be as confident as ever now, O'Flaherty told ET she didn't always feel that way. In fact, she once felt terrified of publicly being her true self.
"As far as girls who aren't out yet, I would say, take the leap," she advised. "I was so scared as well -- it's a lot to build yourself up to, [coming] into your own in the public eye and [to] step into who you really are. But it's so freeing, and I saw most of my success after I came out because I was able to present myself as exactly as who I am."
O'Flaherty also revealed that she actually fell into pageants "by chance" while attending college at the University of Central Florida.
"There was a Miss UCF pageant, and [one year], Sarah York was Miss UCF," she remembered. "I didn’t really know much about her, but I saw her at all of our campus events. I saw how she carried herself with grace and poise, and I just decided that I wanted to be her."
"So, the next year, I enrolled in the Miss UCF program," she continued. "I did very well, and it was through that that I learned about the Miss America organization."
Aside from breaking ground as Miss America's first out lesbian, O'Flaherty also hopes to spend her reign by raising awareness for suicide prevention, a cause she says hits close to home.
"When I was 13, I lost one of my best friends to suicide," she explained. "It was through the grieving process that I realized that there were warning signs and maybe this could have been prevented. So, I’m now an advocate for the American Foundation for Suicide Prevention and also the Trevor Project, which is the nation’s leading crisis intervention and suicide prevention resource for LGBT youth."
"It's really cool for me to merge my suicide prevention efforts with the LGBT community, because I know exactly how it feels to come out," she continued. "So, that’s really exciting and I’m hoping to really be a champion to suicide prevention this year."
As ET previously reported, O'Flaherty sent her first official tweet from the Miss Missouri Twitter account on Wednesday.
"Hey there! Erin here, officially signing in as Miss MO 2016," she wrote. "So excited to serve this amazing state."
This fall's Miss America competition is scheduled for Sept. 11 in Atlantic City, New Jersey. As we patiently wait to see who takes home the crown, watch the video below to hear more on five of the pageant’s most famous contestants.