It's Not The End Of The World
Calderwood was downbeat to see the four-times League Cup winners exit the competition at the first hurdle.
The Reds' did force three good saves from Stanley goalkeeper Ian Dunbavin but the League One side could not find a way through.
Calderwood told the NEP 'Congratulations to Accrington, they have claimed our scalp. I am disappointed and we have got to focus and start again. It is disappointing to lose and be out of the Cup and we did not do enough.
'I ask myself if it was a setback or a catastrophe. I have to say it was a setback because we just did not perform well enough.
'We are doing well in the league but there is always something that comes up and bites you on the backside and it happened tonight.'
Accrington Stanley boss John Coleman would like his side to play in front of the television cameras all the time.
The League Two side has now been on television nine times and lost only once.
But this is perhaps their biggest scalp so far as they saw off two-time European champions Forest in the Carling Cup first round.
Paul Mullin was the Stanley hero with his deflected 61st-minute effort being the winner.
Coleman said: 'There is something about Sky and it is amazing our record on television. I wish we could play on TV every week.
'It is not a shock to me that we won. I always think we will. If you put us up against Manchester United tomorrow, I would have a game plan to beat them.
'I hope it encourages the players to relax. Why be scared of anyone in our league now?
'I think we can play better than that. We can pass the ball and control the game better, but now I just hope for the club's sake that we have a money-spinning second-round tie.'