Billie thought she just had a bad headache. She woke up unable to walk or write.

When 21-year-old Billie Kuczynski came home from a casual bushwalk with her dad, she was hit with a crushing headache.

Within hours, she had collapsed and was fighting for her life in hospital, placed in an induced coma after suffering a ruptured brain aneurysm.

Billie doesn't remember much about waking up after two weeks in a coma. But her mum, Tammy, remembers every single terrifying detail.

Tammy remembers the tears when she realised her girl had come back to her. The panic when Billie had no recollection of how she ended up in hospital. The fear when her daughter had to relearn simple life skills, like how to walk and write again.

So much of her memory was just… gone.

But remarkably, there was one thing Billie knew how to do: dance.

Billie in hospital. Image: Supplied.

Physical Culture, or Physie, was Billie's life.

She'd been dancing and competing for 20 years and more recently started teaching.

But after the coma, she had little recollection of her passion. She knew Physie was something she loved and had done for years, but she couldn't remember any of the dances, songs or classes.

"This was also at a time when, if you asked her an hour after breakfast what she ate for breakfast, she also didn't know that either. Her memory was absolutely shocking," Tammy told Mamamia.

When Billie moved to the rehab ward, her Physie teacher, desperate to find a spark of the old Billie, sent over some routine videos.

"She was like, 'I kind of know this'," Tammy recalled.

But Billie was adamant. She couldn't properly remember the routine; the cognitive memory was simply absent.

"It took about an hour of convincing her, 'Please turn on the music, you'll know it'," Tammy said.

And then, she did.

"She stood up and she could do it all," Tammy said.

Billie's immediate reaction was a stunned, "Oh my god". The 21-year-old was in absolute awe that her body could do something her mind couldn't remember learning.

It was the first undeniable sign that, somewhere inside, the real Billie was still there.

A young Billie. Image: Supplied.

From healthy to holding on.

Just weeks before this miraculous moment, Billie was a fit and healthy 21-year-old nursing student living in Sydney. She was suddenly thrust into the fight of her life.

She'd come home from a bushwalk with her dad when a headache hit. But this was no ordinary migraine.

"I came out to my dad and said I had a bad headache and then I collapsed," she said.

"I began to have a seizure and my dad called the ambulance to get me help."

Tammy had only just arrived in Queensland on a trip with her other daughter.

"In all honesty, Billie's been one of the healthiest people in our lives," Tammy said.

"When my husband called me saying she's unconscious, they can't wake her up, I was still very much downplaying it all, like she'll be fine, maybe it's a migraine.

"I would have never ever thought she'd have something like a ruptured aneurysm."

Billie had to learn how to walk again. Image: Supplied.

The family has no history of brain aneurysms and Billie fit none of the risk factors: family history, heavy alcohol consumption, smoking, high blood pressure and age (typically 45 to 65). It was random.

In the hospital, the team worked quickly. Billie underwent surgery to address the bleed, just as her mum and sister were flying home to NSW.

"I think I was in disbelief for a very long time," Tammy said.

They purposely steered clear of Google.

"I didn't want to be even more scared," Tammy admitted.

"We knew it was a life-threatening thing, but we probably still didn't even grasp the complete seriousness of it… I didn't know how many people die from these."

Ruptured brain aneurysms are fatal in about 50 per cent of cases, according to the Brain Aneurysm Foundation. Of those who survive, about 66 per cent suffer some permanent neurological deficit.

Billie spent two weeks in a coma. Image: Supplied.

Billie spent two weeks in an induced coma — a "terrifying" time for the whole family, who spent 24/7 by her bedside.

"We went from thinking she'd wake up the next day to four weeks of her being intubated and ventilated," Tammy said.

The moment Billie woke up was "ridiculously emotional."

"It was so good," Tammy said.

But they knew she might not be the same. The family was told the right side of Billie's body and her speech would be affected.

Billie had to learn to walk again in the very rehab ward she'd only completed nursing placement just six weeks before.

"That was pretty weird, but looking back, I'm proud that I did that and that I could actually do it," she said.

Billie underwent rehab on the same ward she completed her nursing prac placement at.Image: Supplied.

Back where she belongs.

After six weeks in hospital, Billie was finally able to leave. And she went straight to a Physie class.

"I couldn't remember everyone's names," she said. But the sense of community transcended words.

"I just remember feeling so extremely happy seeing everyone," Billie said.

"Even though my balance was shocking, it just made me feel like I'm back. I'm back to my family, back to my happy place."

For Tammy, seeing her daughter reunite with her dance family was priceless.

"Everybody in the room cried," she said.

"When it first happened to her, they said that she would have problems speaking and maybe couldn't move the right side of her body, but that they wouldn't know the extent of the damage until she woke up.

"In those two weeks, we were preparing ourselves for maybe a completely different person with different abilities, waking up. So then to see her actually be able to do anything that's even close to dancing, was just…"

Billie celebrated the one-year anniversary of her brain bleed with a brain cake. Image: Supplied.

The close call was a wake-up call for Billie. Today, she's calmer, less scared of death and has a new approach to living.

"I just want to live and enjoy every single moment," she said.

The whole experience has taught her the ultimate lesson: to lean on those around her.

"I was very much the person after I got out where I was like, 'No, I want to do this on my own'," she said.

"Sometimes you can have people help you so you can slowly get better. You don't need to rush it."

Feature image: Supplied.