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
Get emergency help for:
Bleeding that is heavy or does not stop with firm pressure
Vomiting blood or passing black, tar-like, or clearly bloody stools
A sudden severe headache, confusion, fainting, seizure, or new weakness
A head injury when you have severe thrombocytopenia
Heavy vaginal bleeding with dizziness, weakness, or fainting
Breathing difficulty, chest pain, or a painful swollen limb
These symptoms may indicate significant bleeding or, in some conditions, a blood clot.
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 prompt medical advice for new petechiae, frequent nosebleeds, worsening bruising, blood in the urine, unusually heavy periods, or bleeding that takes longer than usual to stop.
During pregnancy, report new bleeding, severe headache, vision changes, upper abdominal pain, or sudden swelling promptly.
3
Does any of this apply?
Book an appointment
Arrange routine follow-up if a blood test shows a low platelet count but you feel well and have no significant bleeding.
Follow-up helps confirm the result, compare it with previous counts, and investigate the cause.
Every sign above is quoted from the sofidex article on Thrombocytopenia. If you are not sure, err upward — it is always reasonable to be checked.