The Germany international wasted a big chance to give his side the lead in the 35th minute after a good cross from David Alaba, with Muller putting his close-range header over the bar.
Nevertheless, the 24-year-old feels it would be unfair to blame his miss for Bayern's draw.
"I do not feel responsible for the draw. That's simply not the way things go," Muller told TZ. "The header was not as easy as it seemed to be. I ended up under the ball, which caused it to go over the bar.
"I feel really bad about it, both for the team and for myself. This really hurts. Things like this happen in football. It's hard to really explain it. It should obviously have gone in."
Bayern went top of the table following the draw against Leverkusen and Borussia Dortmund's loss against Monchengladbach at the weekend.