The boy's predicament has been described as a parent's worst nightmare.
So devastated are his mum and dad, they are said to have required medical treatment.
According to his lawyer, their traumatised son has been crying and refusing to eat in the police holding cell where he could spend the next month.
Yesterday Australian Foreign Minister Kevin Rudd pledged to do everything he could "to get this young fella back home".
The boy is the youngest yet in a long line of Australians arrested over drugs on the idyllic holiday island.
Schapelle Corby has served almost seven years of a 20-year sentence. Two of the so-called Bali Nine drug runners face execution.
Mindful of strong rhetoric and public outcries that surrounded those high-profile cases, Rudd and Prime Minister Julia Gillard yesterday adopted a more diplomatic tone.
Rudd said he would work closely with "our friends and colleagues" in Indonesia, and stressed his respect for its laws. "Regrettably, we know the authorities in Denpasar too well through matters we have had to deal with over the years," he said.
"I'm not going to be in the business of providing public lectures from abroad on the nature of anyone else's legal regime."
Australia's ambassador, Greg Moriarty, has flown from Jakarta to lead intense behind-the-scenes efforts to secure the boy's release.
Yesterday Bali-based consul-general Brett Farmer went to the island's police headquarters to discuss the case with senior officials in the narcotics division.
The teen's life was turned upside down on Tuesday afternoon after he and a friend enjoyed a foot massage in the busy resort town of Kuta.
Both boys were arrested by four plain-clothed police outside a convenience store across the road. The shop's owner told smh.com.au the officers had "loitered" there for three hours, and knew who they were looking for.
"They did not search or ask the boys anything," he said. "I remember the boys looking confused and asked why, why were they being taken away."
Police sources told Australian media the teen was carrying 3.6 grams of cannabis. His friend was later released.
The teenager allegedly told arresting officers he bought the cannabis from one of the many Kuta street dealers who openly offer drugs to tourists. He paid 250,000 rupiah ($36) after the dealer said he hadn't eaten for a day and needed money.
The boy's lawyer, Mohammad Rifan, said police should have interviewed the boy with his parents present and questioned the legitimacy of initial urine and blood tests.
He also believes police were tipped off - perhaps by the man who approached the boy.
"Whether [the boy is] being trapped, tricked or not, we're still investigating that," he said.
Under Indonesian law, no distinction is made between drugs such as cannabis and heroin or juvenile and adult sentencing. Although possession carries a maximum 12 years in jail, child offenders typically receive shorter sentences.
Legal opinion is split on how quickly the teen and his family will be able to return to their home in Morriset Park on the NSW Central Coast, north of Sydney.
Melbourne barrister Julian McMahon, who represented Bali Nine ringleader Andrew Chan, is optimistic it will be sooner than later.
"If he is charged at all he would be charged with possession and the maximum penalty would be six years but he would get nothing like that," he told the Australian. "He would get some months, you would expect, if any jail time at all."
Police can hold the boy for up to 30 days without charge.
Usually, Indonesian courts apply leniency only in cases where offenders can prove a drug addiction.
That formed part of an appeal by a New Zealand-born businessman sentenced to seven years' prison for possessing 3.58 grams of cocaine.
Melbourne-based Angus McCaskill was freed in August after 14 months in Kerobokan jail.
Another Victorian escaped a 12-year term after telling judges he had turned to drugs to fight depression brought on by a heart operation.
Caught with 0.06 grams of methamphetamine, Ricky Shane Rawson was released two weeks ago after serving four months.
Yesterday police were reported to be reinterviewing their latest young suspect after his lawyer's complaints. New urine and blood tests were also ordered.
The key decision, on whether to lay charges, was expected soon afterwards.
