Brief Answer:
Self resolving mostly,

Detailed Answer:
Thank you for asking
Dizziness and vertigo of short duration is likely innocuous and a recent flu can cause that too. ear nose or throat infection in near past may cause that. Most of the time it is self resolving and it goes by in a feww weeks.

I would say take some antivert and betahistines for the relief and get some vestibular functions and associated work up to sort out the cause of this vertigo. There are thousands of causes which can cause vertigo . some are central like migraines etc and some are peripheral like vestibular functions disturbance or cardiac perfusion issues or positional vertigos like BPPV. some other causes are

Allergies.
Illnesses such as the flu or colds. Home treatment of your flu and cold symptoms usually will relieve lightheadedness.
Vomiting, diarrhea, fevers, and other illnesses that cause dehydration.
Very deep or rapid breathing (hyperventilation).
Anxiety and stress.
The use of tobacco, alcohol, or illegal drugs.

Nut shell, it is multidimensional and most likely innocuous but it is mandatory to sort out any syncope or inner ear or central causes.

Seek a otorhinolaryngologist if the issues persist despite the symptomatic treatment with anti vertigo medicines.

I hope it helps. take good care of yourself and dont forget to close the discussion.

May the odds be ever in your favour.

Regards
Khan

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