The Germany left back scored Dortmund's winner to down Real Madrid 2-1 at the Westfalenstadion and admits to playing through pain for the entire match.
Reflecting on the win, the 24-year-old told of his joy at finding the net in such a high-profile match, and also how he had played the full 90 minutes after picking up a knock in the warm-up to the game.
"This is of course a dream. This is what you have in mind as a young boy: scoring the winning goal against Real Madrid in the Champions League," he told Dortmund's official site. I am overjoyed. It's been difficult to sleep.
On his recent injury troubles, the defender remarked: "I had pain in the warm-up, but it left as the game went on, and my body was so full of adrenaline, I could avoid the pain. I am very happy that I got through the 90 minutes."
The result leaves Group D wide open, as Manchester City failed to overcome Ajax at the Amsterdam ArenA. Meanwhile, head coach Jurgen Klopp has more injury concerns ahead of Saturday's game against Freiburg, with Sven Bender and Mario Gotze also carrying knocks.
"The time for troubled professionals between two such games is very short," Klopp told Der Western.
When asked of Bender and Gotze's recovery chances, the former Mainz man said: "[Four days] will not be enough."
Ilkay Gundogan is in line to come in for the injured Bender.