While preparing for a performance as the Enchantress in Beauty and the Beast at De Montfort Hall in Leicester, the star was hit by a ladder and knocked out.
She was later carried off in an ambulance and declared too unwell to take the stage.
The 40-year-old performer's rep said in a statement: 'Sam had got a suitcase out for her daughter Brooke who is going on a skiing trip. Her husband Craig was there and called the ambulance but Sam was on the floor for about an hour.'
They added, 'Sam was checked over at Leicester Royal Infirmary then allowed home.'
Bailey shot to fame after winning season 10 of the X Factor UK.
Bailey has since tweeted to let her fans know she is OK.
She tweeted: 'I’m on the mend people!' alongside a photo of her snuggling her dogs.
Wishing Sam a speedy recovery!