Thomas Tuchel's men bounced back from their 2-1 defeat to Eintracht Frankfurt by thrashing Gladbach 4-1 at Signal Iduna Park.
Sahin was named in the starting XI - his first Bundesliga appearance of the season - but lasted just 36 minutes before he had to be replaced by Julian Weigl.
The Turkey international said of the complaint after the game: "I took a knock to my knee relatively early in the match. It was after around 10 minutes or so. Initially I thought that I'd be able to run it off, but it got worse with every passing minute."
Sahin has endured a career punctured by serious injury issues, but his latest knock is nothing serious.
"Luck in misfortune for Nuri Sahin," Dortmund posted on Twitter. "Our number eight has to only take a two-week break due to a knee injury."