"I'd told two or three friends before I told my employer, that was how important it was for me."
In March last year, the hairdresser, formerly known as Ahren, was working at a salon operated by Mensworks owner Matt Swan.
It was known as Barkers Groom Room, but Swan operated independently of Barkers Clothing company, which had an adjacent outlet.
Hemmingson decided to transition to live as a woman so she could later apply for gender reassignment surgery, a decision she hoped her employer would support.
Instead, she was told she was no longer a match for the business and was asked to sign a letter that said: "We would like to mutually agree that due to the situation you have presented to us it would be in the best interests of yourself and the business to end your employment with Mensworks and Barkers Groom Room effective immediately".
She refused to sign it and approached an advocate for advice and to have her case put before the ERA. She is seeking $15,000 compensation for hurt, humiliation and distress.
"That just destroyed me from the inside out and caused me so many anxious issues. When someone tells you who you are doesn't commercially fit, every time you do something with a client you are like 'is this person thinking the same thing that they told me?'
"Hearing that was the most heart breaking thing, because it's a job I've done for so long."
Swan told the Herald on Sunday he didn't accept Hemmingson's claims, but wasn't willing to comment further until the legal process was completed.
Attempts at mediation have so far failed and the case against Swan will be heard by the ERA next month.
Communications manager at Rainbow Youth Toni Duder said the situation was a classic "textbook" case that illustrated why transgender youth ended up over-represented in statistics for depression, homelessness and suicide.
Duncan Cotterill solicitor Catherine Coup said the situation gave rise to potential claims for a constructive unjustified dismissal and gender discrimination.
