The Robins, now eight points adrift at the bottom of the Championship, cancelled out an early Liam Fontaine own goal via Steven Davies' header - only for Craig Davies' late penalty to leave them with nothing to show for their efforts.
O'Driscoll said: "Our performance had everything I would want apart from enough goals to win the game.
"I was disappointed we didn't get a penalty for handball late in the game, but that's the way things have been going for us.
"We have a big summer ahead with a number of contracts up, but I can't ask more in terms of effort than the players showed today.
"The fans have stuck with us, but we have known for a while that a change of strategy was necessary at the club.
"We can't keep on throwing millions of pounds at trying to achieve success. It hasn't worked."