A Brisbane mum's lung cancer symptoms were masked by her pregnancy for months and almost was diagnosed too late.

However, she's warning other mums to not make the same mistakes she did and get tested early.

Samantha Bladwell thought something was wrong as she was 30 weeks pregnant but figured it was to do with the baby.

She would be short of breath in weird situations, such as walking up a hill or giving a presentation at work and had decided to take herself to her GP.

Her GP wasn't convinced but sent her off for tests anyway.

After a CT scan, a biopsy and conversations with specialists, she was diagnosed with stage 4 lung cancer, which was in her spine, her brain and both of her lungs.

“It was very surreal, and all a bit of a blur,” she told Kidspot.

“People assume if you’ve got lung cancer, you smoke, so it’s your fault. I’ve never smoked a cigarette in my life,” she said.

‘The truth is anyone with lungs can get lung cancer. No-one deserves to have lung cancer, it’s horrible.”

She's now urging other mums to get tested as she initially blamed her shortness of breath on the expected baby.

The mother-of-two is now undergoing target therapy which works to specifically kill cancer-causing cells.

Photo credits: Kidspot