Sick Note
A doctor's sick note is not required for absences of less than 14 days. For absences lasting less than 14 days a self–certification note otherwise known as an SC1 form should be completed and returned to your employer. These forms are available from the surgery or the post office.
Legally you are not required to provide a sick note other than a self–certification note for absences less than 14 consecutive days if symptoms persist.