2nd job, no tax deducted

My wife works part time as a nurse earning about £25,000 per year. She did one shift for another surgery where they paid her £270 with no deductions. Is this classed as self employed income and does she have to pur it in her self assessment or is it covered by the £1000 trading allowance? Thanks

Hi,
You can see guidance on the trading allowance here:
Tax-free allowances on property and trading income
Thank you.