The Gladbach talent is delighted with the opportunity of making his debut for his country, while former team-mate Marco Reus has praised his development
With Julian Draxler being ruled out due to a head injury and Bastian Schweinsteiger suspended, the trainer opted to nominate Herrmann, much to the delight of the 22-year-old.
"It's a feeling you can't explain - pure delight. At first, I couldn't believe it," he told Bild.
"For me, it's a dream come true!"
Meanwhile, his former Fohlen team-mate Marco Reus, who now plays for Borussia Dortmund, has backed the decision to give Herrmann a chance to excel in the national jersey.
He said: "Patrick has had some good performances last and this season, he has developed constantly. We welcome him to the squad."
Germany play Kazakhstan on March 26, 20.45CET at the Grundig Stadion in Nurnberg.