The 17-year-old downed seven double espresso coffees while working in the family’s sandwich shop and was left “burning up and hyperventilating”.
Student Jasmine Willis, who thought the coffees were single measures, said the effects of the espresso were so severe her actions left customers bewildered.
She said she started laughing and crying for no reason while serving them, but after being sent home by her father Gary the medical symptoms started. She developed a fever at home and was unable to breathe properly.
Jasmine, of Stanley, County Durham, was rushed to the University Hospital of North Durham after her cousin called the paramedics. Doctors confirmed she had overdosed on caffeine and after monitoring her condition allowed her home a few hours later.
She made a full recovery and wants to warn others about the dangers of excessive coffee drinking.
“My nerves were all over the place,” Jasmine said.
“I was crying in front of the customers and had tears streaming down my face.”
After going home she experienced frightening physical symptoms. She added: “I was drenched. I was burning up and hyperventilating.
“I was having palpitations, my heart was beating so fast and I think I was going into shock.”
After being allowed home from hospital she suffered side effects for days and now cannot face the sight of coffee.
She said: “I felt exhausted for days afterwards. I did not realise this could happen to you and I only hope other people learn from my mistake.”
Her father Gary, who runs The Sandwich Bar, in Stanley, said: “She did not realise she was drinking double measures.
“I have always stressed to my children the importance of moderation but Jasmine got caught out on this occasion.”