The huge demand for youth services is causing long waits for patients, with some practices even being forced to turn new clients away, says the New Zealand College of Clinical Psychologists.
The organisation (NZCCP) said not enough new psychologists were being trained to meet the growing need, so things could get worse before they got better.
Lena Watt was 16 when her mum took her to a GP, because she was worried about her mental health.
"By the time I reached the GP, it was really a crisis point, I was already self-harming and really I just needed help yesterday."
She was struggling with depression and needed professional help as soon as possible.
The month and a half she spent waiting to see a specialist was a very difficult time, Watt said.
"It was terrible, I felt like I had no one to reach out to. My mum obviously had no experience or training with this kind of thing."
Her mum eventually set her up with a private psychologist, which - while helpful - was expensive.
Concerned for those unable to pay to get the help they need, Watt and her mum decided to walk the length of New Zealand to raise money for youth mental health charity 'I am Hope.'
She now works part-time for the organisation.
NZCCP executive advisor Paul Skirrow said stories like Lena's were all too common.
"We're hearing stories of long waiting lists, and in some cases waiting lists being closed for child and adolescent mental health services in particular."
The mental health conditions which people were waiting weeks or months to get treatment for were often very serious, Skirrow said.
"Something that's life-threatening where somebody's suicidal, being told that, well, there's no service for you just is absolutely heartbreaking."
There had been a worldwide spike in demand for psychological services in part due to the Covid-19 pandemic, as well as economic uncertainty and the climate crisis, Dr Skirrow said.
New Zealand was not training enough psychologists to keep up, he said.
"It's kind of worrying for us really, because we think there needs to be a big boost in investment and then continued investment."
In the past, people could reliably see a private psychologist if they had the money, but now waiting lists for these practices were backed up too, Dr Skirrow said.
'If you're focused on crisis, all you're going to get is more crisis'
I am Hope charity founder Mike King said New Zealand's mental health system was too focused on crisis, rather than helping young people before they reached breaking point.
"In other words, a child has to be in crisis before they can see a mental health professional. And if you're focused on crisis, all you're going to get is more crisis."
Improving access to counselling services would help to ease the load on the country's psychologists, King said.
"So what we need is a proactive model, where young people can go and see a counsellor, not when they're mentally unwell, they go and see a counsellor to stay well."
Lena Watt said she was too young to worry about the specifics of the system, but was in no doubt something needed to change.
"I can't give you an exact answer when it comes to the number of psychologists or whether it's pay or whatever, I'm 18 I don't know that kind of thing. But I can tell you from a child's perspective that it's not good enough,"
"I felt like I was completely ignored, like there was no one out there that could help me."
Te Whatu Ora mental health service executive clinical director Paul Oxnam said it offered multi-disciplinary teams, including psychologists, and because of this, it did not hold psychology-specific waitlists.
When a person is referred to a service, they are triaged, and people who need acute care are always prioritised and seen urgently.
"There may be a delay in accessing a psychologist due to reasons such as increased demand or staff pressures - including staff illness, or needing to care for unwell dependents - however people under our care are always supported by other clinicians," Oxnam said.
None of their child or adolescent teams had closed their waiting lists at this time, he said.