Unwell
Not well or in good health, ailing, sick, indisposed.
For example, 'I am well-nigh choked with the sulfurous heat of the weather -- or I am unwell.' (1826, Journal of Sir Walter Scott) 'Unwell' is also a euphemism for experiencing menstruation.
It medicalizes women with the implication that the menstrual period is always a time of illness.
It is no longer appropriate usage (if it ever was).