"I am frustrated on one hand, but on the other hand we could have also lost the game," manager Eddie Howe said.
"Keeping a clean sheet away from home is positive, but having our third game without scoring is certainly negative.
"We don't normally struggle to score but today at least we did not struggle to create chances.
Afterwards, Flores praised his side's defending but admitted his players are "nervous" in front of goal.
"Defending well is a good base, but I feel when we are in the opposition's box that the players are still a little bit nervous and they can sometimes make bad decisions," he said.