Hi Dear ,
As per your query you have problem unsteadiness after waking along with hypokalaemia which can further cause weakness and nausea . Well there can be many reasons for unsteadiness along with hypokalamia , but the most common is anxiety and the other Benign paroxysmal positional vertigo (BPPV) are 
ear infection , 
hypoglycemia , anemia , meniere's disease , migraine , cervical spondolysis , sinusitis and alteration in he blood circulation . For now do not bend forward , try to eat one banana daily as its contain hight amount of natural potassium , drink plenty of water and drink green tea thrice a day with ginger .I would suggest you to 
consult ENT specialist again if condition doesn't get better for proper examination . Doctor may order test like rotatory chair test , head movement test , 
posturography , 
blood test , examination with otoscope and CT scan . Doctor may prescribe antiemetic drug , sedatives , antibiotics like gentamicin and recommend balance therapy , vestibular therapy.
Hope your concern has been resolved.
Get Well Soon.
Best Wishes,
Dr. Harry Maheshwari