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 if facial pain occurs with:
If you feel you may act on these thoughts, contact emergency services or a crisis service immediately.
Ask for prompt medical advice if you develop new persistent facial numbness, weakness, hearing changes, balance problems, or pain on both sides.
Difficulty eating or drinking because of repeated attacks also needs timely help.
Seek urgent same-day assessment for facial pain with a blistering rash near the eye, a red painful eye, or new vision changes.
These symptoms may have a different cause that needs rapid treatment.
Arrange a routine medical appointment if you develop repeated, shock-like facial pain, particularly when touch or chewing triggers it.
You should also seek review if a diagnosed pain pattern changes, attacks become more frequent, or treatment is no longer controlling them.
The article also says
Severe, recurring pain can sometimes lead to hopelessness or thoughts of self-harm.
Every sign above is quoted from the sofidex article on Trigeminal neuralgia. If you are not sure, err upward — it is always reasonable to be checked.