Barker admitted his Town side were slow out of the blocks as they bowed out of the Johnstone's Paint Trophy with a 1-0 defeat at Griffin Park, coming after Saturday's 2-1 league reverse.
Super-sub Sam Saunders did the damage in the 73rd minute, latching on to Scott Barron's left-wing cross to fire home from 10 yards.
"It's disappointing because we wanted to progress and the old clichi that we can concentrate on the league is not really a consolation," he said.
"I said on Saturday that winning is a habit that you don't want to break and now we've lost twice here, so we have no option but to put it behind us and focus on our next league game."
