Ms Armstrong said a nurse took a urine sample for a test. Once the test was done, they threw the test into a bin, gave Noah an icy pole, panadol and nausea medication. A doctor diagnosed him as "having a bug".

“The doctor came and basically said kids just get pain sometimes. Nothing more.”

Ms Armstrong then took Noah home but the boy remained curled up on the couch, screaming and losing control of his limbs within five minutes of returning from the hospital.

She said Noah began losing consciousness, couldn’t talk or walk, and she rushed him to Perth Children's Hospital where she informed staff of Noah’s alarming condition.

The nurses at PCH rushed to perform an ultrasound, X-ray, urine test, CAT scan and blood test, and called for the pediatric surgeon. The tests ran from Wednesday night to Thursday morning.

“The CAT scan showed his appendix had burst and that he had a malrotation of the bowel (intestinal). He needed immediate surgery," Ms Armstrong explained.

“They put him on IV fluids. He then went straight to the operation theatre. It went on for more than three hours since they had to fix two issues quickly in one slot.”

Ms Armstrong said Noah’s bowel has been rearranged and his appendix removed.

He is currently tired on morphine but doing well. He will be in the hospital for up to ten days.

Ms Armstrong said she hoped Noah would be released by his fourth birthday, December 23.

A spokeswoman for St. John of God Midland said the hospital was reviewing the matter and would communicate with the family. Due to privacy laws, they were not able to divulge any further details.

WAtoday has also contacted Perth Children's Hospital for comment.

Ms Armstrong said she hadn't left her son's bedside at PCH since Wednesday.

"He's my son. I would rather be by his side, no food or sleep, for as long as he needs me. I'm glad the doctors and nurses here are amazing," she said.

She said her son's ordeal in the healthcare system was a wake-up call for her.

“It’s so upsetting that the doctor took a look at my three year old, experiencing some alarming symptoms, and decided, 'oh yep, go home'. How can they gamble a child's life like that?," she said.

“There was no further testing done at all. I had to watch a piece of myself struggle and I was begging to fix him.”

“If you have a child. Please, please do not let anyone turn you away if you do not think they are okay. I could have lost my son if I listened to them,” she wrote.