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 with you has:
Severe difficulty breathing or rapidly worsening breathing
Stridor while resting
Blue, grey, or unusually pale lips or skin
Pauses in breathing
Marked drowsiness, confusion, or difficulty waking
Severe chest pulling between or below the ribs with each breath
Inability to speak, cry, or drink because of breathlessness
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
Arrange prompt same-day medical assessment for fever with a harsh cough, new noisy breathing, worsening symptoms after a viral infection, or breathing that is faster or harder than usual.
A child who is drinking much less, passing less urine, or becoming unusually sleepy also needs prompt assessment.
3
Does any of this apply?
Book an appointment
Routine follow-up is appropriate after recovery if cough or hoarseness is gradually improving.
Make an appointment if symptoms are not continuing to improve, return after treatment, or interfere with normal activity.
The article also says
Keep the person as calm and upright as possible while waiting for help.
Do not force them to lie down or inspect their throat.
Every sign above is quoted from the sofidex article on Tracheitis. If you are not sure, err upward — it is always reasonable to be checked.