McSharry finished third in a tight final, which was won by South Africa’s Tatjana Smith with Tang Qianting second for China.
The 23-year-old looked in shock as she checked the screen to see where she had finished, as her quiet confidence about securing a medal in Paris became a euphoric reality.
“It’s amazing,” the Sligo swimmer told BBC Sport NI after winning Ireland’s first medal in the pool since the Atlanta Games in 1996.
“It’s amazing to be part of a race with such tight competitors. To come out and watch the Irish flag being raised, and to be part of that atmosphere, was unbelievable.
“It’s something I’m never going to forget.”
McSharry still looked in disbelief as she stood on the podium some 20 minutes after the conclusion of her race as the Irish flags dominated the Parisian arena.
After stepping off the rostrum, she ran to a group of Irish flags in the corner before taking some time to savour her historic moment.
“You can’t really ask for anything more than winning a medal at the Olympics,” she added.
“I’m not even sure that was really something that little me dreaming of going to the Olympics thought was possible.
“I’ve kept pushing and that’s what I’ve been training for all year, to be top three and dreams do come true.”