WASHINGTON — First lady Melania Trump spent a low-key birthday at the White House Sunday after what her husband described as a “traumatic” shooting at the gala White House Correspondents’ Dinner the previous evening.

The Slovenia-born Melania, who turned 56, was “holding up well” despite Saturday night’s scare, a spokesperson told The Post Monday.

The first lady’s East Wing staff gave her flowers and a card to mark the occasion, while the White House posted a message on social media reading: “Happy Birthday to our amazing First Lady of the United States, Melania Trump!”

Melania’s birthday followed the shooting at the dinner held at the Washington Hilton and preceded the state visit by the British king and queen , which begins Monday.

Melania Trump in the press briefing room as the president briefs reporters on Saturday’s shooting attempt AFP via Getty Images

The first lady was sitting between her husband and White House press secretary Karoline Leavitt at the top table when authorities say 31-year-old…