Doubled over in agony, Leah Dunbar struggled to concentrate on what her college tutor was explaining in class.
For two weeks, the 17-year-old criminology and forensics student had been experiencing increasingly excruciating pain when passing urine and had lost more than a stone in weight.
"I had been eating normally but I was exercising too so I put my weight loss down to that," says Leah, who is now 19 and lives in Southampton. "But I went from 8.5 stone to 7 stone, and it was still coming down. I thought the urinating pain would just pass and that it was perhaps a urine infection, but when it started to interfere with going to college, I made an appointment with my doctor."
At the surgery, Leah underwent a urine test, which showed there was glucose present in her urine. The nurse then carried out a finger prick test and to her shock, Leah was told that she has suspected Type 1 diabetes.
About 400,000 people are currently living with the condition in the UK, including around 29,000 children. Type 1 diabetes is when the body’s immune system attacks and destroys the cells that produce insulin and is controlled by daily insulin injections. Famous people with the condition include actress Sharon Stone, Olympian rower Sir Steve Redgrave and former UK Prime Minister Theresa May.
Today ahead of World Diabetes Day (14 Nov) Leah is speaking out to warn others about the dangers and how to spot the symptoms.
"When the nurses took me into a different room and said they'd have to call an ambulance to take me to A&E, I was in shock," she says. "I didn't expect anything like this. I was just expecting to be prescribed some antibiotics and then head home. I was feeling really worried."
Once at Southampton General Hospital, the teenager underwent more tests and stayed in overnight before she received a positive diagnosis. She was told that she couldn’t leave the hospital until she could show the doctor she was able to inject insulin. But Leah, already a needle-phobic, found it difficult.
"The first time the nurse had to do it for me as I didn’t want to do it," she says. "But the second time, I did it myself as I was so desperate to go home," she says. "It was a little bit scary, but my mind was telling me just to get on with it."
Today, Leah has to monitor what she eats on a daily basis and inject herself with insulin before meals. The diagnosis also forced her to change her career path, as she was told her dream job of working as an engineer in the army would no longer be possible.
Having the condition also means Leah is more at risk of developing chronic kidney disease (CDK) – which affects about 1 in 10 people in the UK. It is known as the ‘silent killer’ because it is usually asymptomatic until it has reached an advanced stage. Those with the condition have a greater risk of having a stroke or heart attack.
It can also cause kidney failure, when sufferers will need to have dialysis and a possible transplant.
Watch: Strictly's Nadia Wadia on her son's battle with Type 1 diabetes
"I have to check my kidneys regularly, because my diabetes makes me more susceptible to kidney failure," Leah says. "But whenever I would go to the hospital or the GP, they would make me urinate in a cup for a test, and that can be really embarrassing walking around with it in front of strangers."
Now, in a bid to tackle the ticking time bomb of CKD, the NHS has linked up with Healthy.io, a health tech company to target 650,000 at-risk people like Leah across the UK. It allows them to test for CKD at home using a phone app and testing kit.
"My GP sent me a message asking if I wanted to try the at-home urine testing kit," said Leah. "When I got the kit, I found it very easy to use and the app was installed on my phone."
Thankfully, Leah’s kidneys got the all clear. "It is amazing to get instant results and know my kidneys are fine, as well as it taking away the embarrassment of walking around with a jug of urine in public."
A diagnosis of Type 1 diabetes might be life-changing but Leah has some words of advice.
"It’s fine to be in denial, I was. Confidence comes with time and acceptance.
"Don’t beat yourself up about not wanting to be a diabetic. There will be some days that you just want to feel normal, because I did for about the first year. I was in complete denial and didn’t really want to face up to it.
"And I’m still getting there. I had 17 years of eating “normally”, then pretty much overnight, everything changed. But I’m getting there, and one day I’m sure I’ll have it all completely sussed."