The 55-year-old singer shared a tearful post on Instagram admitting he missed his children on the road and questioned his ability to keep going.
Donald said: "Sorry but this post will be all over the place! (As is my head)
"I’m on the come down as It’s been a highly emotional morning after the first performance at the King's Coronation at Windsor castle.
"Black and white photo hiding the red eyes and the few tears I cried while FaceTiming my wife and kids this morning.
"It really is truly overwhelming and I always ask myself after 30 odd years am I really cut out for this?! The nerves, anxiety and handling the fame whilst being in the public eye after such a massive tv performance."
The Everything Changes singer shared a picture of himself on stage performing at King Charles III's Coronation concert and then another close up of his face in black and white, with tears in his eyes.
He added: "The appreciation of the public and the applause from all the talented orchestra, choir, drummers after a rehearsal is truly heart warming!
"Maybe I can handle this for a few more years to come… why not!"
Donald has two young sons — Bowie, born in 2016, and Dougie, born in 2017 — with illustrator wife Katie Halil.
He also has two daughters Lola, 23, and Grace, 18, from previous relationships.
He confessed in 2020: "I've really struggled in the 50s being a father. I’ve actually really taken it physically and mentally draining for me.”
The Relight My Fire singer added: "“I would advise, me at this moment in time, I would advise to fathers who maybe already have children that may be in their teenage years, don't do it.
“In [your] 50s don't do it.”
"I'm sure there's people out there in their 50s that have found it a doddle, maybe they've got, you know, babysitters and nannies and stuff like that, maybe not, maybe they're really struggling as well, but I've really struggled with it and I would never advise anyone in their 50s to have young children.”
Donald joined boyband Take That in 1990 aged 22.
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