Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
1
Is any of this happening now?
Call 911
Call emergency services if a lump or swelling comes with:
Trouble breathing or swallowing, especially with mouth, tongue, face, or neck swelling
Sudden severe testicle pain or swelling
A pulsing abdominal lump with sudden severe abdominal or back pain, weakness, or fainting
Other emergency signs, for anyone
Someone who is struggling to breathe, gasping, choking, or cannot get words out
Someone who has chest pain, tightness or pressure lasting more than a few minutes
Someone who has sudden weakness or drooping on one side of the face or body, slurred speech, or sudden confusion
Someone who is unconscious, or cannot be woken
Someone who is bleeding heavily and it will not stop with firm pressure
Someone who has had a seizure that will not stop, or does not wake up afterwards
Someone who has lips or skin that look pale, blue, grey or blotchy
Someone who you believe has taken an overdose or swallowed something poisonous
2
Is any of this happening?
Be seen today
Seek same-day medical care if a lump is red, hot, increasingly painful, or accompanied by fever.
These signs may indicate an infection that needs treatment.
A painful groin or abdominal lump that becomes firm, cannot be gently pushed back, or occurs with vomiting or severe abdominal pain also needs urgent assessment.
This can happen when a hernia traps part of the bowel.
Arrange follow-up sooner if you also have unexplained weight loss, drenching night sweats, ongoing fever, or unusual tiredness.
3
Does any of this apply?
Book an appointment
Book a routine appointment if a lump:
Lasts longer than about two weeks
Is growing or keeps returning
Feels hard or does not move
Causes ongoing pain
Is in the breast, testicle, or neck
Appears without a clear explanation
And for anyone, someone who:
has noticed a lump, a mole that has changed, or unexplained weight loss
Every sign above is quoted from the sofidex article on Lumps. If you are not sure, err upward — it is always reasonable to be checked.