Dexter Blackstock equalised Guirane N'Daw's opener after 58 minutes but further goals from Luke Hyam and Daryl Murphy ensured Ipswich moved clear of the relegation places.
"I was going to make a change after 20 minutes, but that's probably a bit too radical," said O'Driscoll. "I could have brought anyone on. I just needed to change things.
"I wanted to change the formation but, to be fair to them, they've been on a great run and we got a great result (a 2-1 victory) at Wolves on Saturday but in this league, if you get one win everyone thinks they're superstars.
"If you don't put the hard work in, that's the kind of performance and you get well and truly beaten.
"You can never take anything for granted in this league. It baffles me and I'm not happy.
"There were mistakes all over the pitch, in every area. We lost the ball from our kick-off and that gave them a start. Ipswich then gained momentum."