A mother is sharing her “traumatic” experience of dealing with multiple misdiagnoses before her young son was ultimately diagnosed with cancer.

Ffion Smith said her 8-year-old son, Ruben Troy, experienced body pain, bruising, mobility issues and weight loss before his diagnosis of acute lymphoblastic leukemia (ALL), an aggressive blood and bone marrow cancer, according to Kennedy News and Media.

The concerned parent claimed doctors, for multiple visits, initially chalked it up to a bad diet and prescribed her child an over-the-counter medication that helps treat upset stomachs, acid reflux and heartburn.

“We were a bit relieved at first because they said he’d got gastritis, and they told us to give him Gaviscon,” the mom said of the early visits.

Smith, 28, continued, “We noticed it was making no difference and they said, ‘There’s no need for anything else. It’s his stomach, it’s hurting.’ ”

“They just said he must have a lot of acid in his stomach and that’s what’s hurting him,” she added. “They were saying that it was his diet that was the issue and all that was triggering the gastritis.”

The lead-up to the doctor’s visits was scary for Smith and Ruben, who are from Northallerton, North Yorkshire, England.

Ruben complained of back pain starting in April.

A few days later, the 8-year-old collapsed while playing with a friend before he began crawling and screaming in pain, so Smith took him to urgent care, where she claims a doctor said it was a sickness bug.

After Ruben later collapsed again, he felt chest and back pain, which doctors then thought was the misdiagnosed gastritis.

Over time, Ruben began looking pale, experienced bruising across his body, struggled to walk normally and lost more than 20 lbs.

“I can’t get my head around it — it’s so traumatic that it makes me feel sick when I think about it,” Ruben’s mom said. “It makes me feel so angry that the doctors just wouldn’t listen.”

The leg pains and mobility issues also forced Ruben to miss school.

“Some days it’d be really bad, and some days it’d be bearable where he’d walk a bit. He would be screaming,” Smith recalled. “He was in so much pain and we were giving him Calpol and Nurofen, but nothing would take away the pain and he’d just lie in bed all day.”

On June 29, Smith urged doctors to perform blood tests, which revealed Ruben had acute lymphoblastic leukemia.

“We are still in shock from it,” Smith admitted. “We never thought in a million years [it would be cancer]. Now, he has to use a wheelchair — as soon as he stands up, he says his legs are stinging.”