The One Show presenter bruised her ribs while attempting a lift with partner James Jordan and spent two days visiting a physiotherapist for treatment
"It was absolute agony and I have been in a lot of pain," Jones told the Sunday Mirror.
"We tried to do a lift and I just felt a shooting pain in my back. I've been to the physio and they said I've badly bruised my ribs. Afterwards I could barely walk.
"Even after all these weeks my body is still not completely used to some of the movements and they can be a real strain, but this is by far the worst injury I've had."
Jones danced the American Smooth to Roy Orbison's 'Pretty Woman' on last night's Strictly Come Dancing, receiving a score of 34 out of 40.
She recently described her One Show co-host Matt Baker, who competed in Strictly Come Dancing last year, as her fifth judge.
> Alex Jones: 'Strictly Come Dancing beating X Factor is amazing'