When the family went to visit him at the police station next day, they had to speak to him through glass, she said.
"He was just, tears in his eyes. That was a massive thing for him to go through, to be in a police cell, he's never done that before."
The court ordered he be sent to ward 21 at Palmerston North Hospital, then transferred to Rahatangi Adolescent Inpatient Unit in Porirua, but both facilities rejected him, saying he did not fit their criteria.
The court then ordered he be put into Child Youth and Family care over night, and while it was still not the appropriate place for him, there were no other options.
The next day an empty house was sourced for the teen to stay in, but the family were given no assistance to care for him.
His father is currently staying with him in the house.
His mother is anxiously awaiting court on Monday to find out if there is a residential programme he can be placed in that will address his behavioural needs.
"There's just not enough in this country for these kids," she said.
The family had been struggling for some time, trying to get support. They also have younger children at home and needed to be able to keep everyone safe, she said.
"He just needs the help that he needs that I can't give him.
"We do want him back but he needs to be safe and we need to be safe with him."
Police confirmed a 14-year-old boy spent a night in custody on Wednesday "due to other appropriate accommodation being unavailable that night."
Autism New Zealand board member Wendy Duff said "the whole thing is appalling, basically."
"It's just another example of what's happening around the country."
She said there needed to be "safe havens" for people with autism spectrum disorders where they could go and be surrounded by a team of people trained to deal with them, such as a therapy team and psychiatrist to look at medications.
Duff said she was aware of a number of families "bubbling away, just ready to tip over into crisis" because they were not being supported properly.
"It's spiralling," she said.
"I don't think Ministry really have opened their eyes to how big it is out there and how it's just going one family to another."
Duff was hoping to see a "good outcome" on Monday that would see the teen placed into care with professionals who could help him.