There are a number of official channels to pursue if one of the listed practitioners has harmed you in some way, or acted unethically. I will not respond to complaints, but rather direct you to this list of resources. Where possible and safe, please discuss the issue directly with the practitioner, before escalating to professional bodies.
AHPRA
Australian Health Practitioners Regulation Agency is the organisation responsible for the implementation of the National Registration and Accreditation Scheme across Australia. They help direct complaints to the National Boards
The 15 National Boards are:
Professional Associations
Professional Associations often have codes of ethics that bind their members. They can be an avenue for seeking more information and advice around a complaint.
APS - Australian Psychological Society
AAPI - Australian Association of Psychologists Incorporated
RACGP - The Royal Australian College of General Practitioners
SAS - Society of Australian Sexologists
AASW - Australian Association of Social Workers
PACFA - Psychotherapy and Counselling Federation of Australia
ACA - Australian Counselling Association
SSEAA - Somatic Sex Educators Association of Australia
ANZACATA - Australian, New Zealand, and Asian Creative Arts Therapies Association
Discrimination Complaints
You may also decide to file a complaint, you may make one with Victorian Equal Opportunity and Human Rights Commission, Australian Human Rights Commission, or Victorian Civil and Administrative Tribunal (VCAT).
Victorian Legal Aid have a good guide on how to choose whether to pursue this process, and how.