The 25-year-old Saturdays' singer was preparing for this weekend's show with dance partner Kevin Clifton.
She was obviously giving it her all as one couple will be voted off during Sunday's episode of the competition.
Frankie uploaded a picture of Kevin attending to her injury, writing: "Ouch!! My 1st Strictly injury."
THE SATURDAYS: 'WE'RE JUST LIKE OTHER WORKING MUMS'
While the injury doesn't look to be that serious, it's probably the last thing Frankie needs ahead of the weekend.
Her nerves are already setting in, with her tweeting earlier this week: "Well this dance is hard! Feeling the fear for Saturday already! Maybe we could sit this weekend out and do ours the week after?!"
But, just like us, Frankie knows just how to cheer herself up. After he injury, the mum-of-one headed to McDonalds to get herself some comfort food.
While she shared a snap of her bag of food, and blamed Caroline Flack for her turning to fast food, all we could notice was her HUGE wedding bling.
If the burger and fries isn't enough to make her feel better, staring at that rock will surely do the trick...