A persistent cough which lasted for two weeks led her to her GP in June 2013; she received antibiotics for a chest infection.
The following day, she was fighting for her life in hospital as pneumonia turned to sepsis and her organs started to shut down.
In a last-ditch bid to save the mum of one from Lochwinnoch, Renfrewshire, a consultant was flown up from Leicester and an ECMO machine used to save her.
It worked but the damage had already been done and Cor’s hands and legs, below the knee, were amputated.
Waking up in hospital, Cor had to quickly come to terms with her new normal and her brothers suggested she set up her own charity.
The 49-year-old recalled: “Davie (52) and Scott (45) felt I had to find some sort of purpose. I was at rock bottom and feeling useless.
“I thought it might help me to help other people in the same position – and that’s absolutely what it has done.”
Initially, Cor thought she would simply offer peer support to other amputees.
But Finding Your Feet, the charity she launched in January 2014, has gone on to do much more.
There are now some 60 clubs up and down the country which meet monthly, with five main groups in Aberdeen, Dundee, Glasgow, Edinburgh and Ayr.
Cor said: “I initially met other amputees for a coffee or lunch because I knew what it felt like to be in the same position.
“I had no idea what to expect and no-one could tell me – I wanted to fix that.
“There are now around 60 clubs a month, including climbing, swimming, yoga, ski-ing, gardening and crafts.
“I refused to organise coffee mornings as I’m too young for that! So we set up ampu-teas instead, allowing people to meet others in an informal setting and make new friends.
“We also offer counselling and therapy sessions to help people build confidence.
“I’m not vain in the least but I couldn’t wear the same clothes I used to and I really struggled to find my look.
“Long sleeves, buttons and zips were all out.
“It can be really hard to look the way you want to look and feel good about yourself when your choices are much more limited.”
Cor quickly amassed a small army of volunteers who were willing to donate their time to the cause.
Thanks to generous donations from the public and sponsors, the charity also now employs one full-time member of staff and seven part timers – five of whom are amputees.
Around 300 people attend the clubs monthly, with 6000 people signed up on the charity’s website.
Initially, due to data protection, Cor struggled to find amputees to help.
However, building links with NHS Scotland means that recruits are now signposted to the charity.
Cor explained: “I naively thought I could get a list of amputees from the NHS but that wasn’t possible.
“However, we linked up with the West of Scotland Mobility and Rehabilitation Centre (WestMarc) in Glasgow and the Smart Centre in Edinburgh.
“When your rehab came to an end, that used to be it. I found that really difficult and I’m pretty determined.
“So we talked WestMarc into doing transitional meetings with us.
“We did that for two years, talking to people about a whole range of issues.
“Now, we’re involved from the very start so that people know that, once their rehab is finished, their next step is Finding Your Feet.
“I even get referrals from my own surgeon who calls me direct!
“Medical staff recognise the work that we do helps make their patients and their own lives easier so they are happy to recommend us.”
Often, trying to get the amputees to recognise that they need help is the hardest challenge – something Cor very much relates to.
“If someone said they wanted to help me, I put my defences up,” she said. “I felt that I didn’t need their help.
“So I understand some people are like that. If you ask them if they want a coffee, they’ll likely say yes though.
“We’ve had a few, like me, who were really stubborn and it has taken me years to convert them!
“But they’re now great friends and the difference in them is incredible.”
It’s hard not to be inspired by Cor, though, who also lost a lung two years ago due to her original sepsis diagnosis.
And she made headlines in January last year when she became the first person in Scotland to receive a double hand transplant.
It meant she could hold her son Rory (11) once again.
While she is still learning to use her new hands, she is grateful for her donor’s gift and the support she has received from her son, brothers and mum and dad, Doreen and Colin.
She added: “I’m one of the lucky ones. I’m very grateful that someone who was less fortunate was willing to give me this incredible gift.
“I coped well with my stumps but it’s lovely to be able to hug Rory again.
“I bought the house next door to mum and dad to help them in their old age but we help each other now.
“My family have been incredibly supportive.”
Paul is sharing his story as a warning to school pupils
Paul Johnson is just one of the many amputees who is now helping Finding Your Feet spread the word. He regularly shares his story with school pupils.
A misadventure with alcohol led to Paul’s legs being amputated and he uses that experience as a warning to young people.
Initially, he wanted nothing to do with Finding Your Feet but he now leads the art, design and public relations work.
Cor said: “In the beginning, Paul didn’t even want to meet me.
“He was drunk when he ended up on a railway line and lost both legs as a result. He now talks to school pupils, warning them about the dangers.
“He’ll never know if he’s saved a life but if sharing his story can divert one kid from doing what he did, he’s happy to do so.”
Paul also helps those who have lost limbs to trauma.
Some 40 per cent of all amputees lose limbs due to diabetes and they have their own support workers too.
Cor added: “We match people up with similar journeys. We’re lucky to have enough volunteers to do that now.
“Paul was reluctantly supported by Finding Your Feet and is now paying it back. It’s so rewarding to see that.”
If you would like to support the charity, either financially or by volunteering your time, visit findingyourfeet.net.