Fullkrug's late season form, despite a row with manager Graham Potter, has earned the veteran a recall from Germany coach Julian Nagelsmann.
“It was a tough season, a difficult season, but I'm very thankful for the trust from the coach (Julian Nagelsmann) and I will try to take responsibility and pay it back because I'm always happy to be there,” Füllkrug said.
“I think ‘difficult' is the right word to describe my season. It didn't go how I hoped, but I’m glad we had a little positive feeling to finish the season.
“I missed so many games, and I played so many games without 100 per cent fitness that season, so I'm happy about every game."
I wish season didn't end
Fullkrug continued: “I would also have been happy if the season continued and we didn't have a summer break, but it is how it is. It was difficult, but now I look forward in the future, and I see positive things in front of me.
“I was very unlucky with the injuries, and because of that, I missed almost every chance to play again for the national team. I was fit for maybe six weeks or something in between both my injuries, so I couldn't really reach my best form, but now I feel very good, I feel strong and I'm ready to play 90 minutes, and that makes me happy.
“I'm so happy to be with the national team, and I'm really looking forward to playing with the team because we have incredible players.
“It's a very nice team to be a part of, a very nice culture, very positive and I will get energy there.”