"We are enjoying a moment now that I'm not sure we can repeat," he told UEFA.com. "Tonight we played well and stood up to Madrid's pressure. In the end we got the result we needed to get to the final.
"We have fought a lot in order to reach Wembley. Even after conceding twice tonight we were only thinking of the final. Madrid are a magnificent team and it's very hard to come here and not concede.
"The important thing was the result, though. There was a lot of joy in our dressing room. We wanted to get to the showpiece and we did it."
Dortmund will face either Barcelona or Bayern Munich in the final later this month.