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
Seek emergency care if the lump becomes suddenly very painful, firm, or cannot flatten when you lie down, particularly if you also have vomiting, abdominal swelling, or cannot pass stool or gas.
These symptoms can occur when part of the bowel is trapped in a hernia and its blood supply may be affected.
Sudden severe pain involving the groin and testicle, especially with swelling, nausea, or a testicle sitting higher than usual, also needs emergency assessment.
This may be testicular torsion, in which the testicle twists and loses blood flow.
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
Get urgent same-day medical advice if:
The lump is red, hot, rapidly enlarging, or leaking pus
You have fever or feel significantly unwell
Pain is increasing or limits normal movement
The lump pulses, especially with pain, weakness, or faintness
3
Does any of this apply?
Book an appointment
Book a routine appointment if the lump lasts longer than about two weeks, keeps returning, or becomes larger, harder, or fixed in place.
You should also arrange an assessment if swollen nodes occur with unexplained weight loss, drenching night sweats, or no clear infection.
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 Groin lump. If you are not sure, err upward — it is always reasonable to be checked.