Queen Elizabeth II will not attend the thanksgiving service in her honor this Friday.
The 96-year-old Queen felt "some discomfort" during the celebrations and will "with great reluctance" miss the ceremony at St Paul's Cathedral, Buckingham Palace said on Thursday evening.
However, the ceremony planned for Thursday evening in Windsor, at which the Queen should light a beacon, will continue to take place, it said.
Quoting Buckingham Palace's official statement, the BBC said: "The Queen thoroughly enjoyed today's birthday parade and flying in formation, but felt uncomfortable at times.
With a view to the journey she must take to attend tomorrow's thanksgiving service at St Paul's Cathedral, the Queen has been reluctant to choose to stay away from the service.
The Queen looks forward to seeing the bonfire at Windsor Castle tonight and thanks everyone who made today a special memory for her."
The monarch appeared twice on Thursday on the balcony of her London city palace, Buckingham Palace.
She was seen smiling and obviously in a good mood.
However, the Queen has been suffering from mobility problems for months and has repeatedly canceled important events.