The German will now miss the Clasico clash against Real Madrid next Sunday due to his red card, but was in a buoyant mood after his team's fighting spirit secured three crucial points.
"It was a fantastic match. It's very important to see how we got the three points for the future. This gives us confidence, and I'm very happy for the team," said Flick, who led Barcelona to the league title last season.
"We created a lot of chances, but if we're honest, Girona created a lot in the first half. The next few games are very important for us."
Defender Araujo proved the unlikely hero, coming off the bench in the 82nd minute before finding the net in added time. Flick was full of praise for the versatile Uruguayan's contribution.
"I'm very happy for Araujo. His attitude when he plays, what he gives to this club and this team. He can play in that position at certain times. I asked him before he came on if he could play there, and he said yes," Flick added.
Despite his red card, Flick couldn't contain his emotions when the winner went in.
"The celebration wasn't directed at anyone; it was because of how we had won. I was happy. I don't do anything against anyone, and I never will. I accept the referee's decision," Flick said.