Helen Flanagan has apologised for posting a picture online of her posing with a gun to her head in the aftermath of the US school massacre.
The former I'm A Celebrity...Get Me Out Of Here! contestant, 22, said she had been "careless" and that the Twitter episode had been "humiliating".
She told ITV1's Daybreak: "It was just relating to a hangover that I had and then I tweeted it and I started getting all these reactions of, 'how insensitive, how could you do this?', and I just felt sick.
"I just deleted it straight away, I rang my best friend and I was like, 'I can't believe what I've just done', and I said to her, 'shall I reply to these saying how sorry I am?'
"And then I thought no, it will just draw attention to the fact of completely what I've done - it's so humiliating."
The former Coronation Street actress decided to republish the snap - which has now been removed from the site and showed her wearing a black, lacy bra - after originally posting it in October.
She told Daybreak: "I absolutely hated myself for it. I am incredibly sorry and I couldn't be more sorry... I think what I did was ridiculously stupid... it was the stupidest thing I've ever done - I would never, ever want to hurt anyone."