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 or severe difficulty breathing
Blue, grey, or very pale lips or skin
Choking with an inability to breathe, speak, or cough
Severe chest pain, collapse, or loss of consciousness
Sudden marked weakness with difficulty staying awake
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 medical advice for new or quickly worsening breathlessness, a weak cough during a chest infection, repeated choking, difficulty swallowing liquids, fainting, or a new fast or irregular heartbeat.
Morning headaches, unusual daytime sleepiness, or disturbed sleep can be signs of shallow breathing overnight and also need prompt assessment.
3
Does any of this apply?
Book an appointment
Arrange routine follow-up if weakness, falls, pain, stiffness, or fatigue are gradually increasing.
Also mention skin problems from braces, unwanted treatment effects, weight change, or equipment that no longer meets your needs.
The article also says
Children with delayed movement skills, frequent falls, or loss of previously gained abilities should be assessed.
These signs can have many causes and do not by themselves confirm muscular dystrophy.
Every sign above is quoted from the sofidex article on Muscular dystrophies. If you are not sure, err upward — it is always reasonable to be checked.