"It was a really tough game, but we expected to create more chances than we have done," he told Sky Sports 1.
"But having said that we probably carved out the best chance, the best piece of football in the game, when John Carew had a chance cleared off the line.
"But overall it was tough and I thought they have played to get something out of the game and I thought our effort was terrific. We kept going right to the end.
"We have a habit of scoring goals, but also letting a few in at the other end, so I thought today, if we kept a clean sheet, we would win - but it wasn't to be.
"But we'll learn a lot because that's a big, tough game for us, physically it was demanding and we'll have gained from that."
Having seen Gareth Barry's move to Liverpool fail to materialise, O'Neill was delighted the midfielder received the full backing of the Villa faithful.
"It was fantastic, as it has been ever since he came on as a substitute against Odense in the qualifying rounds for the Uefa Cup," he said.
