Every single team has the occasional poor game and poor result. We've won every match since. Perhaps that loss was just what we needed in order to not get complacent this season.
Add to this, Marchisio is now back, Dybala is in form, Higuain has gotten into shape, Pjanic is still being integrated, etc... Our season is on the up and up, and we've won 8 of our first 10 matches in the league and CL. We've had a very good start to the season.