The Germany international created the opener for Jarrod Bowen, though Saints earned the point in injury-time through Lesley Ugochukwu.
“I’m very angry today, not disappointed, just angry on what we did after the goal,” Füllkrug told the club's webstie. “I'm very, very angry that we played like this because we had some minutes where we showed what we can do against an opponent like that at home.
“I think there were 25 to 30 minutes in the second half which were very good and we showed that we can have very good possessions, that we can go in behind, and that we could have the chances to score again.
“It's not the first time that we scored a goal and... we don't try to play (possession) football anymore, we don't push up anymore, we just sink and that's not the way we want to play.
“When we can play 65 minutes before with possession, even if it's not perfect, we tried to play with possession, we tried to create chances, we tried to score and then we scored a goal and after that, that's not the way it works.
“We have to find a way to have a togetherness, to have the idea of where we want to go, what we want to do, and the coach is very clear in what he wants but we have to do it all,+ everyone has to do it. It’s just my feelings today.”