The 20-year-old England midfielder had already won over Madrid's faithful with four goals in three away wins to start the season after joining the club this summer.
But on Saturday Bellingham was gifted a fumbled save by Getafe's goalkeeper David Soria right in front of the goal, allowing him to tap home a stoppage-time winner and save the hosts from a stumble in their home debut at a newly-renovated Santiago Bernabeu Stadium.
The 2-1 comeback kept Madrid at the top of the Spanish league with a perfect record.
Bellingham said the celebration by Madrid's supporters, which included singing The Beatles classic "Hey Jude," made him tremble with emotion.
"That is the loudest moment I have been in at a stadium and happily it was after my goal," Bellingham said. "I can't believe it to be honest. When they were singing 'Hey Jude,' I just wanted to turn and listen – my legs were shaking.
"I know that I was brought in for these kinds of moments, and I've just got to keep doing it and making sure the fans go home happy."
Madrid lost veteran top scorer Karim Benzema to the emerging Saudi Arabian league this offseason and was able to bring in Joselu Mato only when Kylian Mbappé stayed put at Paris Saint-Germain.
Joselu, whose Espanyol was relegated last season, and Bellingham provided the goals to fight back against Getafe who went ahead in the 11th when Borja Mayoral poached a bad pass by new Madrid left back Fran García.
Bellingham's five goals in four games, including a double in a 3-1 comeback at Almeria two weeks ago, lead the league scoring list. That is compared to his eight goals in 31 Bundesliga appearances last season.
"We are not surprised by the talent of (Bellingham), but I am surprised that he is scoring so many goals," Madrid coach Carlo Ancelotti said. "Everyone is surprised, even him."
Getafe are being scrutinised for having acquired forward Mason Greenwood on loan from Manchester United after the English player left his old club following a criminal investigation into a possible attempted rape that was closed by prosecutors.
The deal was announced just before the summer market closed on Friday. The 21-year-old England forward has not played for United since January 2022.
Getafe coach José Bordalás said in the post-game news conference, "It is a very delicate situation that is not to be made light of. … Everyone knows what happened and the measures that were taken. We can only talk about soccer. He is motivated to be here and we will help him recover his best level."