The Catalan outfit hit the woodwork four times during the La Liga clash at the Camp Nou, but a second-half strike from Joaquin Larrivey secured all the points for the visitors.
"It was a crazy game and we had many chances to score," he told Sport.
"Now we have to look forward. We know we'll get criticism, that's how it works. I know my game wasn't good.
"We were disastrous against [Real] Madrid and better here. Now we try to correct our defects as a team. I'm not worried. These things happen in competition . We have to be prepared for times like this."
Barcelona have now lost their last two in the league and are third in the table.