Mark Brook thought he was fit and well. A routine health check at his GP just weeks before had given him the all-clear. Then, one summer evening, everything changed.

The 53-year-old from Bassetlaw experienced a sudden stroke that left him feeling underwater. His vision blurred. The world began to spin. Mark went to bed hoping the feeling would pass, but when he woke the next morning, the symptoms remained.

After a fall and double vision, his daughter recognised something was seriously wrong. She contacted NHS 111. The next day, Mark was assessed at Doncaster Royal Infirmary, where CT scans, a CT angiogram and MRI confirmed he had experienced a stroke.

He spent six days on the Hyper Acute Stroke Unit receiving specialist care and physiotherapy. Now, several months on, Mark has made a full recovery and regained his vision.

"I never thought this could happen to me," he said. "They were phenomenal angels. I couldn't fault any of them."

Mark's experience is unusual because his symptoms were not the typical FAST signs people are taught to recognise. There was no facial drooping, arm weakness or speech difficulty. That is why he is speaking out during Stroke Awareness Month.

"If something feels unusual, it's always best to get it checked," he said.

If you think someone is having a stroke, call 999. If you are unsure, contact NHS 111.