The Azzurri booked their spot in Sunday's final to take on Spain thanks to a double from Mario Balotelli, who benefitted from poor German defending to send one of the tournament favourites home empty-handed.
Despite picking up their performance and rallying late on through a Mesut Ozil penalty, Hummels believes the Mannschaft ultimately left themselves too much to do against quality opposition.
"We screwed up in the first half," the 23-year-old told reporters after the game. "Two-nil down against a team who are so tactically good is difficult."
Hummels, who enjoyed a successful domestic season as his Borussia Dortmund side secured a league and cup double, felt his personal performance was not up to par for a match of such magnitude as he took responsibility for the opening goal.
"For the cross for the first goal I didnít do well enough," he added.
"That the cross even went in was my fault so I played a big part in the first goal."