The 22-year-old from Lenzie, East Dunbartonshire, was caught trying to smuggle 24lb (11kg) of cocaine with 23-year-old Michaella McCollum, from Dungannon, Co Tyrone, in August 2013.
The pair - nicknamed the “Peru Two” - were jailed for six years and eight months after admitting the offence.
Reid admitted she had lied to police after her arrest that she had been coerced at gunpoint to carry the drugs in a bid to lessen her punishment.
She returned to Scotland on Wednesday after spending nearly three years in a string of hellish Peruvian prisons.
Reid told the Scottish Mail on Sunday how in summer 2013, aged 19, she had flown to Ibiza with a friend to spend the summer on the Spanish island.
But the holiday turned into a spiral of taking hard drugs and clubbing that led her to a British woman acting as a recruitment agent for drug smuggling gangsters.
She was offered 5,000 euro (£4,100) to fly to Argentina, spend a few days sightseeing and return to Europe with a package in her luggage.
“I thought it sounded like a challenge and was blase about it,” she told the newspaper.
“I was offered 5,000 euro but it wasn’t just about the money. I had saved up before I left Scotland so I had cash for rent.
“I didn’t owe any money or anything. I just wanted to be able to boast about it.”
Reid said that she “wasn’t in the right state of mind” and living a “ridiculous life”.
“[I] wanted to show I could manage it. I now realise that I put myself at risk and no one would have known where I was if anything had happened to me, but I didn’t care at the time.”
Reid flew first to Majorca where she met McCollum for the first time.
After two nights in a house with a group of armed gangsters she moved on to Madrid, where she was told she would be going to Peru instead.
“I just went along with it. The guys had guns but I was never threatened,” she said.
Reid was arrested as she tried to pass security at Lima airport on her return with the cocaine packed in her suitcase.
Her mother, Debbie Reid, described the moment she found out in a telephone call: “[They said] ‘Mrs Reid? It’s the Foreign Office here. Are you sitting down? I’m afraid your daughter has been arrested in Peru for drug-smuggling.”
In an attempt to reduce her culpability Reid followed instructions the gang had given her before her departure - that she had been forced to smuggle the drugs against her will.
“We thought we would be believed and it would all go away, but we were wrong,” she said.
McCollum and Reid faced the prospect of a maximum 15-year prison term but struck a behind-closed-doors plea bargain to secure the shorter sentence.
Reid, who was deported from Peru under an early release scheme, said she had been an “easy target” for the gang who she fears will seek her to recoup their losses.
“My life will never be the same,” she said, adding that she wants to raise awareness and warn other young people not to get involved in drugs.
McCollum was freed in March under new legislation but was required to remain on parole in Peru.