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
Seek emergency help now if you or someone you are caring for has:
Severe difficulty breathing, gasping or an inability to speak normally
Blue, grey or unusually pale lips, face or skin
New severe confusion, collapse or difficulty waking
Severe or persistent chest pressure
A seizure
A baby with pauses in breathing
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 worsening shortness of breath, dehydration, coughing up blood, a fever that returns after improving, or chest pain when breathing.
New confusion in an older adult also needs prompt assessment.
3
Does any of this apply?
Book an appointment
Arrange routine follow-up if recovery has stalled, coughing or breathlessness is not gradually improving, or tiredness continues to limit normal activities.
Follow any individual oxygen-monitoring plan provided by a healthcare professional.
The article also says
Babies, pregnant people, older adults, people with weakened immune systems and those with serious heart or lung conditions should seek advice early if pneumonia is suspected.
Every sign above is quoted from the sofidex article on Viral pneumonia. If you are not sure, err upward — it is always reasonable to be checked.