The 29-year-old scored twice in his side's 4-1 away win against Fortuna Dusseldorf on Saturday to take his tally to 18 goals in the league this season, two behind the division's top scorer Robert Lewandowski of Borussia Dortmund.
"Last week he was three ahead," Kiessling told Bundesliga.com. "To be honest, it doesn't really bother me too much.
"I try to help the team with my goals and commitment. But of course I wouldn't mind being top goalscorer at the end of the season."
Bayer are currently third in the Bundesliga with 48 points from 27 matches.