“There was a discussion about whether I should or shouldn’t. And I was like, f— it,” Lopez tells PEOPLE of wearing the Tamara Ralph gown

The head-turning gown Jennifer Lopez wore to the Unstoppable world premiere almost stayed at home!

Stopping by the PEOPLE/Entertainment Weekly suite the day after the sports biopic’s Sept. 6 premiere at the Toronto International Film Festival, Lopez, 55, told PEOPLE why she ultimately decided to wear the revealing dress — a sparkling, silver Tamara Ralph gown with head-to-toe side slits tied together with oversized bows — out on the town.

Put simply, she tells PEOPLE, “I felt good.”

“There was a discussion about whether I should or shouldn’t. And I was like, f— it,” she laughs of the gown.

After walking the red carpet, the “On the Floor” singer gave fans an even closer look at the show-stopping look on Instagram, showing it off from several angles.

“Toronto #TIFF2024 #UnstoppableMovie,” she wrote alongside one post, which she followed up with another simply captioned, “Unstoppable.”

The actress followed the dazzling premiere look — which she rounded out with a metallic Judith Leiber clutch, Hassanzadeh jewelry and Dolce & Gabbana platforms — with a more subdued, monochrome ensemble.

On Saturday, Sept. 7, Lopez returned to the festival (and stopped by PEOPLE’s photo studio!) in an all-green look by Burberry — including the brand’s Leather Saddle High Boots, an olive sweater and a pleated maxi skirt with a high-knee slit in a slightly more muted shade.

While showing off the more understated, fall-forward outfit, which she accessorized with brown sunglasses, gold jewelry and a snakeskin handbag, on Instagram, the star shared a sweet message about the Unstoppable premiere — which also marked her first major public appearance since filing for divorce from husband Ben Affleck on Aug. 20.

“Still on a high from last night at #TIFF2024! It was such an incredible experience being surrounded by so much talent and passion for #UnstoppableMovie,” she captioned the post. “Grateful for every moment and the amazing energy of the city.

Also at TIFF, Lopez compared the premiere of William Goldenberg-directed Unstoppable — which was produced by Affleck as well as his longtime pal Matt Damon — to the 2019 premiere of her film Hustlers.