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 sudden shortness of breath, chest pain, coughing up blood, fainting, or severe breathing difficulty.
These symptoms can occur if a blood clot reaches the lungs.
A cold, very painful, pale hand with sudden weakness or loss of movement is also an emergency because blood flow may be severely reduced.
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 urgent same-day medical care for:
Sudden swelling, pain, tightness, or blue-purple colour in one arm
New prominent veins around the shoulder or chest
A hand that becomes unusually cold, pale, or blue
Rapidly worsening hand weakness or loss of feeling
3
Does any of this apply?
Book an appointment
Arrange a non-urgent medical assessment if you have recurring arm pain, tingling, numbness, heaviness, or weakness, especially when symptoms are linked to arm position or overhead movement.
These symptoms have several possible causes, so an assessment can help identify the source.
Every sign above is quoted from the sofidex article on Thoracic outlet syndrome. If you are not sure, err upward — it is always reasonable to be checked.