Mueller scored his first German league goal since the end of April when he tapped home Arjen Robben's pass to claim Munich's fourth goal in a 5-0 home romp against Wolfsburg -- hours before Bayern's Christmas party.
"It felt good. It's nice that the goal drought is now over," said the Bayern star who had been scoring in the Champions League and in Germany internationals.
"But the goal wasn't as important to me as some people had made out and I felt good after our last few games.
"Of course, you want to score, especially when it's expected from you, but I didn't make as much of it as some people wrote about it.
"I knew my team and the club need my goals, so I will always hang in there."
Mueller was the league's third top-scorer last season with 20 Bundesliga goals, behind only Bayern's Robert Lewandowski and Dortmund's Pierre-Emerick Aubameyang.
He revealed that Bayern chairman Karl-Heinz Rummenigge had bet he would score.
"Before the game, I had a bet with Mr Rummenigge, he backed me and now I have to pay up," said Mueller, without giving away any details.
Bayern's victory had the double-effect of boosting confidence and reclaiming top spot in the league table, which Bayern had lost three weeks ago to RB Leipzig.
Leipzig's shock 1-0 defeat at Ingolstadt allowed Bayern to cut the three-point gap and go top on goal difference.
Both teams are now on 33 points and set to meet at the Allianz Arena on December 21.
"It has the nice side-effect that we can now control our games," said Mueller.
"We lead the table and this is sure to be a good thing for our Christmas party tonight.
"We've played quite well in our last few games and we want to be first in the league when we see what's under the tree (at Christmas)."