When the Queen doesn’t show up for a gig, keen royal observers know something serious is happening. When Queen Elizabeth II canceled a trip to Northern Ireland at the last minute, many wondered what was happening. 

As it turns out, there was a cause for concern. The 95-year-old was taken to the hospital Wednesday for “preliminary investigations” and was then released Thursday, Buckingham Palace confirmed. 

"Following medical advice to rest for a few days, The Queen attended hospital on Wednesday afternoon for some preliminary investigations, returning to Windsor Castle at lunchtime today, and remains in good spirits," Buckingham Palace said in statement.

But she appears to be on the mend, and is expected to lead a royal delegation to a global climate summit with world leaders in Glasgow in a few weeks. Queen Elizabeth has been on the throne since 1952, when she was 25, and is the longest-serving monarch in British history. Her son, Prince Charles, 72, is next in line. 

Some wonder if she’s overdoing it with public duties, but she is reportedly devoted to her work. The Queen also raised brows after being spotted using a walking stick, the first time she was seen with a cane in decades. (The last time she’d recently had surgery). She also has no tolerance for jokes about her age. Recently, she declined an honor of being named "Oldie of the Year" by a British magazine, saying she didn't meet "the relevant criteria." She "politely but firmly" declined the award through her assistant private secretary with "warmest best wishes." 

"Her Majesty believes you are as old as you feel, as such The Queen does not believe she meets the relevant criteria to be able to accept, and hopes you will find a more worthy recipient," Tom Laing-Baker said in a letter.

In other Queen Elizabeth news, the island of Barbados has elected its first former female jurist—Sandra Mason—as head of state, a symbolic position held since the 1950s by the Queen.