The Arsenal forward told reporters: "I am not at all satisfied. We knew it was not going to be an easy game, but we should have scored as we created numerous opportunities.
"We were not efficient with our finishing. But, despite the defeat, I think we played well because we created so many chances.
"It was a special, emotional game for me. I was born in Poland but I wanted to score against them and I was close but my shot unfortunately hit the crossbar."
The loss was Germany's first in 19 competitive outings, dating back to their semi-final defeat at Euro 2012.