Liza Turner “got more and more irate” when he refused her the cash and finally went into the kitchen of his Smith Street home, picked up the knife, and walked out, on April 5.
“Her stepfather asked for the knife back, but she didn’t hand it over,” said prosecutor Robert Carr.
Police spotted her “in a distressed state” at 6.15pm, on Adams Way, and when they asked her if she had a knife, she produced it from her pocket.
Mary Dixon, mitigating, said Turner, who suffers from attention deficit hyperactivity disorder (ADHD) and has mild learning difficulties, intended to harm herself.
“But during the walk home she thought about all her friends, and that stopped her,” she said.
“ I think you can differentiate this young woman from carrying a knife in a gang setting. It seems the only person she harms is herself.”
“I would hope that would sway you enough to step back from a custodial sentence.”
Turner, 20, of Willoughby Court, admitted possession of a blade when she appeared at Mansfield Magistrates Court, on Friday.
Chair Keith Ward said: “The carrying of a knife is a very serious offence.
“If you come back to this court for a second offence the starting point is six months’ custody.”
She was given a 12 month community order with 20 days of a rehabilitation activity requirement.