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 bleeding that is heavy, spurting, or does not stop with firm, continuous pressure.
Get emergency help if bleeding occurs with fainting, confusion, severe weakness, breathing trouble, chest pain, or pale, cool, clammy skin.
Emergency care is also appropriate for:
A deep or gaping wound, an amputation, or an embedded object
Suspected internal bleeding after a serious injury
Vomiting blood or passing black, tar-like stool with weakness or dizziness
Sudden severe headache, confusion, or drowsiness after a head injury
Heavy vaginal bleeding during pregnancy, especially with pain or faintness
And for anyone, someone who:
is bleeding heavily and it will not stop with firm pressure
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 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 advice for blood in urine, coughing up blood, repeated vomiting of small amounts of blood, or rectal bleeding beyond a small streak.
Get prompt advice if you take a blood thinner and develop unusual bleeding or have a significant injury.
3
Does any of this apply?
Book an appointment
Book a routine appointment if bleeding or bruising keeps returning, has no clear cause, or takes longer than expected to stop.
Arrange assessment for unusually heavy periods, bleeding between periods, or any vaginal bleeding after menopause.
Every sign above is quoted from the sofidex article on Bleeding. If you are not sure, err upward — it is always reasonable to be checked.