Friends and family have demanded the release of Kylie Bretag, who was celebrating her 30th birthday with a month-long trip overseas when things went horribly wrong.
Following the advice of a number of travel blogs, Ms Bretag tried to save money by crossing the border into Mexico on foot from California. The border crossing is popular with Americans visiting Mexico for the day.
She has told her family Mexican officials never stamped her passport, despite her repeated requests.
She continued travelling in Mexico for two weeks but was detained on October 20 after immigration officials boarded her bus at a checkpoint in Tenosique and checked her passport.
Ms Bretag has since spent six days at a Mexican detention centre.
Her mother Colleen Bretag said the family are "very on edge".
"It was a dream trip and it's all gone horribly wrong," she said.

Ms Bretag had been due to meet her best friend, Natalie Wayt, in Cancun the day after she was detained.
Ms Wayt, 26, has now launched an online campaign to raise awareness about her friend's detention and call for her to be deported.
"She hasn't done anything wrong," Ms Wayt told Fairfax Media from her home in Los Angeles.
"At the end of the day she was just trying to save a few dollars and it ended her up in jail."
Ms Bretag still has her mobile phone and has been in contact with friends and family via email.
She told her friend Mexican officials have repeatedly said she would be deported or transferred but it never eventuated.
Kylie Bretag, a young Melbourne woman currently detained in Mexico.
"The guards keep saying 'tomorrow'," Ms Wayt said.
"I'm just worried that she's going to be stuck there indefinitely. She's been given false hope over and over again."
Typically, the punishment for travelling without a visa in Mexico is voluntary repatriation or deportation with the possibility of a small fine.
The Department of Foreign Affairs and Trade have confirmed they are providing consular assistance to an Australian in detention in Mexico.
The latest word from consular officials is she will be transferred to Mexico City on Tuesday morning local time, her mother said.
Ms Bretag, a former chef, moved to Melbourne from Canberra four years ago and had recently finished a degree in public relations at RMIT University.
Ms Bretag is being kept in a small and crowded cell with women and children.
She hasn't been allowed outside and sleeps on a foam mat on the floor with the other inmates.
She told her family she hadn't showered since her arrival because there was no privacy and washing only consists of using a bucket of recycled water.