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 if muscle pain occurs with chest pressure, serious trouble breathing, fainting, new confusion, or sudden inability to move part of your body.
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 care if you have:
Severe muscle pain or weakness with dark, tea-coloured urine
Much less urine than usual after intense exercise, overheating, or injury
A rapidly swelling, firm, very painful limb
Fever with a red, hot, swollen, or increasingly painful area
Severe pain after a major injury
New calf swelling or pain with shortness of breath
These signs do not confirm a particular condition, but they need prompt assessment.
3
Does any of this apply?
Book an appointment
Arrange a routine appointment if the aches keep returning, continue for several weeks, steadily worsen, disturb sleep, or limit daily activities.
Also book an appointment if they began after starting or changing a medicine, or if you have ongoing weakness, joint swelling, unexplained weight loss, or prolonged morning stiffness.
Every sign above is quoted from the sofidex article on Muscle aches. If you are not sure, err upward — it is always reasonable to be checked.