A 93rd minute own goal from Gerard Pique cancelled out Seydou Keita's strike for Barca.
"It's upsetting not to win and you always risk being hurt when the scoreline is so close," said Guardiola. "But now we must recover, pick ourselves up and focus on the Champions League in Russia (against Rubin Kazan).
"We knew we should have been tighter at the back. We lost two points in the end, but I'm happy with the performance of the team."