Hi,
Welcome to health care magic,
I have read all your query and understand the issue.
Dizziness even in sitting position is concerning.
Here,it could be due to variety of causes or it could be transient.
Kindly tell me 'Do you have any other symptoms with this dizziness'?
Perhaps if the dizziness is not troubling your day to day work, then you may wait for few days.
Until then you may take proper hydration and electrolyte balance with some symptomatic antihistamines treatment like betahistidine but do not get panic.
However if the problem is persistent, you should see a doctor at the earliest and get evaluated further.
I will suggest you undergo routine blood count,
ESR, blood electrolytes, tests for vestibular (balance) system like electronystagmography or rotation tests to diagnose the cause for dizziness.
Your local physician or GP will know about the test.
He/she will can order the test after complete history and thoroughly clinical examination like temperature, pulse, blood pressure which will enable us to arrive a diagnosis.
Treatment is mainly depend on the underlying cause.
Regards,