The 88-year-old experienced an agonising delay for care after being referred to hospital for urgent treatment by her GP.
The Modbury Heights resident was driven to the new Lyell McEwin Hospital emergency department at 2.45pm on Monday suffering a painful leg ulcer.
She waited 90 minutes in a queue to be triaged, then the real waiting began.
"We're just sitting there thinking, 'surely we've gotta be next, we've gotta be next'," her son Alexander Zadow said.
Ms Zadow didn't see a doctor until 12.45am on Tuesday, 10 hours after she arrived.
"There would've been two dozen people that went up to the window at one point or another and said how long do they have to wait for, there would've been a dozen people that left that I heard saying, 'this is ridiculous'," Mr Zadow said.
The hospital couldn't even provide his mum with a free cup of water.
"How hard is it to get a cup to get free freaking water in the new emergency department," Mr Zadow said.
At the same time, ambulances were ramped outside that hospital and the Royal Adelaide in the city centre.
"Paramedics have contacted us throughout the day yesterday and last night saying it was their worst day in living memory," Opposition Leader David Speirs said.
The government said there were 40 per cent more triple zero calls than on any usual Monday.
Health Minister Chris Picton insisted the problem was being addressed, pointing to the construction of a 32-bed facility at the Repat Health Precinct in Daw Park.
"I would provide assurance to any family that we have moving every mountain possible to put in place the additional capacity that we need," he said.
But the Zadows have already lost faith in the system.
"I will not put my mother through that again, I won't put myself through that again and that next time if we need it, we will ring an ambulance," Mr Zadow said.
Most of Adelaide's major hospitals were again in code white during the day on Tuesday, meaning they were over capacity, but most had eased by evening.