Gotze and his teammates squandered a number of good chances in the 0-0 first-leg draw against Malaga, and he admitted that he will be thinking about some of the "sitters" for a while.
"If you look at the way the game went, then it's definitely not [a good result]," Gotze told Bundesliga.com. "We had a lot of great opportunities and we just lacked a clinical finish. That applies to me more than anybody.
"The decisiveness was probably lacking. They weren't just half-chances, but real sitters which we've really got to take. Now we've got to put it behind us because we've got a pretty good position for the second leg in front of our own fans.
"Of course it'll be going through my head for a while, but I can't change it anymore. I've got another 90 minutes on Tuesday to put it right."
Before the return leg Dortmund host Augsburg in the Bundesliga.