The midfielder called the FA's ruling "ridiculous" and said that he was left "gobsmacked" when he learned the referee's decision would not be overturned.
"I thought it was a foregone conclusion that it would be overturned and I would be available for last nght. Everyone thought the FA would put it to bed that way," he told mixlr's official QPR call-in.
Derry missed his side's 3-0 win over Swansea City through suspension, but was confident that his ban would be lifted for QPR's trip to West Bromwich Albion this weekend.
"I lined up in the training session to play, then I got a call from our assistant manager Mark Bowen who said it had been turned down and I was absolutely gobsmacked.
"To miss out on the next game is ridiculous, really."
QPR face West Brom at The Hawthorns on Saturday at 3pm.