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 severe breathing difficulty, heavy bleeding that will not stop, collapse, or a sudden neurological problem such as loss of movement or consciousness.
Seek urgent medical help for rapidly worsening swallowing, dehydration, a sudden major change in eyesight, new facial weakness, or bleeding that is difficult to control.
Arrange a routine medical appointment for an unexplained neck lump or persistent symptoms such as one-sided nasal blockage, repeated nosebleeds, reduced hearing in one ear, or blood-stained nasal discharge.
These symptoms often have causes other than cancer, but they should be assessed if they do not settle.
If you have already been treated, contact your cancer team about a new lump, worsening swallowing, persistent new pain, unexplained weight loss, or symptoms that return between planned follow-up visits.
And for anyone, someone who:
Every sign above is quoted from the sofidex article on Nasopharyngeal cancer. If you are not sure, err upward — it is always reasonable to be checked.