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 you have very heavy bleeding and feel faint, confused, short of breath, or unusually weak.
Get emergency help for bleeding with:
Severe or worsening pelvic or abdominal pain
Fainting, marked dizziness, or pale, clammy skin
Possible pregnancy with one-sided pain or shoulder-tip pain
Sudden heavy bleeding during pregnancy or after giving birth
A serious injury to the vagina or pelvis
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
Bleeding that soaks through a pad or tampon every hour for more than two hours also needs urgent help, particularly if you have dizziness, chest pain, or breathing difficulty.
If you are pregnant or could be pregnant, contact a healthcare service promptly about vaginal bleeding.
The urgency depends on the amount, pregnancy stage, pain, and other symptoms.
3
Does any of this apply?
Book an appointment
Book a routine appointment if bleeding repeatedly occurs between periods or after sex, your periods have become difficult to manage, or bleeding lasts longer than usual.
Any bleeding after menopause should be assessed promptly, but it is not usually an emergency unless it is heavy or accompanied by severe symptoms.
Every sign above is quoted from the sofidex article on Vaginal or uterine bleeding. If you are not sure, err upward — it is always reasonable to be checked.