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 medical help if you have:
Sudden or rapidly worsening groin or abdominal pain
A painful lump that becomes firm or will not go back in
Vomiting, abdominal swelling, or inability to pass stool or gas
Red, purple, or dark skin over a groin lump
Severe weakness, faintness, or confusion with these symptoms
Do not eat or drink while waiting for emergency advice if urgent surgery may be needed, unless a healthcare professional tells you otherwise.
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
Does any of this apply?
Book an appointment
Arrange a routine medical appointment if you notice a new groin or upper-thigh lump, even if it is painless or disappears when you lie down.
You should also seek routine assessment for repeated unexplained groin pain.
The article also says
Contact the surgical service or a healthcare professional after repair if you develop increasing wound pain, spreading redness, drainage, fever, difficulty passing urine, or a new bulge.
Every sign above is quoted from the sofidex article on Femoral hernia. If you are not sure, err upward — it is always reasonable to be checked.