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 now if you have bleeding along with:
Fainting, confusion, or difficulty staying awake
Severe weakness, breathlessness, or a rapid heartbeat
Cold, pale, or clammy skin
Heavy or repeated vomiting of blood
Severe chest or upper abdominal pain after vomiting
Trouble breathing
If possible, tell emergency staff about blood thinners, aspirin, anti-inflammatory medicines, alcohol use, and any recent vomiting.
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
Vomiting blood or passing black, sticky stool needs urgent medical assessment, even if the amount seems small.
It is not possible to judge the source or severity reliably at home.
After treatment, contact your healthcare team promptly if black stools return, you vomit blood again, dizziness worsens, or you cannot keep fluids down.
3
Does any of this apply?
Book an appointment
Routine follow-up is appropriate when you are recovering without further bleeding but have scheduled blood tests, anemia treatment, medicine review, or care for the condition that caused the vomiting.
The article also says
Do not drive yourself if you feel faint or unwell.
Every sign above is quoted from the sofidex article on Mallory-weiss tear. If you are not sure, err upward — it is always reasonable to be checked.