A Rainworth dinner-lady was caught twice over the drug-drive limit after she smoked cannabis in the day, magistrates heard.
Amber James's Hyundai was seen speeding on Heather Lane, Ravenshead, and when it was stopped officers could smell cannabis, at 10pm on March 18.
A blood test revealed she had 4.7 mcgs of the drug in her system, when the legal limit is 2 mcgs.
Mary Dixon, mitigating, said James, who had no previous convictions, did not realise she would be over the limit.
"She suffers from anxiety and depression and had only just started using it to calm her down," said Mrs Dixon.
"She has since gone to her GP who has increased her medication three-fold."
She said James, a dinner lady at a local school, will now have to get to get a taxi to work and to transport her mother, who she cares for.
James, 28, of Tudor Crescent, admitted the offence when she appeared at Mansfield Magistrates Court, on Thursday.
She was fined £100, with £85 costs and a £30 government surcharge. She was banned for 12 months.
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