Sidwell opened the scoring in the first half with a deflected 19th-minute strike, ending a 317-minute wait for a Fulham goal.
"I can't put my finger on it," the midfielder said of the drought. "We were working hard, creating openings and obviously when you have somebody like Berba (Dimitar Berbatov) in the team, he is always going to create chances.
"We've had that in previous games but just not finished them and we have been letting in goals in Brede's absence so it just all piled on top.
"But now we have this win, we've got two goals under our belt and can kick on. We've got another massive game against QPR on Saturday."