The former Saint-Ettiene forward scored a hat-trick for his new club yesterday, becoming the first man from Gabon to play and score three in the Bundesliga.
"I really noticed the intensity of the Bundesliga," Aubameyang told the club's official website.
"It's far more intensive than Ligue 1. The tempo is higher, but it didn't cause me any problems.
"I like being in Dortmund and I want to work hard week in, week out, and then we'll see what we can achieve this season."
Dortmund are second in the league after the first round of fixtures.