Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
Call emergency services for sudden severe headache with vision loss, fainting, confusion, or one-sided weakness.
These symptoms need emergency care whether or not hair growth is present.
Seek same-day medical advice if coarse hair develops rapidly over weeks or months with a clearly deepening voice, substantial new muscle development, or enlargement of the clitoris.
These changes may signal a rapid rise in androgens.
Arrange a routine appointment if the hair is new, increasing, or upsetting you.
Seek assessment if you also have irregular or absent periods, troublesome acne, scalp hair loss, difficulty becoming pregnant, or symptoms that began after starting a medicine or supplement.
The article also says
Unwanted hair alone is rarely an emergency.
Every sign above is quoted from the sofidex article on Excessive or unwanted hair in women. If you are not sure, err upward — it is always reasonable to be checked.