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 for sudden severe abdominal or back pain, especially with fainting, marked weakness, clammy skin, breathing difficulty, or a pulsing abdominal lump.
Do not drive yourself if you feel faint or seriously unwell.
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 urgent medical care if:
The lump becomes painful, tender, firm, or red
A suspected hernia no longer flattens when you lie down
You have fever, vomiting, or increasing abdominal swelling
You cannot pass stool or gas
Pain is persistent or getting worse
And for anyone, someone who:
has abdominal pain that is severe, constant, or getting worse
3
Does any of this apply?
Book an appointment
Arrange a routine appointment if the lump is new and unexplained, remains present, or keeps returning.
It should also be checked if it is growing, hard, fixed in place, or accompanied by ongoing pain, appetite loss, unexplained weight loss, or changes in bowel or bladder habits.
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 Lump in the abdomen. If you are not sure, err upward — it is always reasonable to be checked.