Brief Answer:
Pathology in Vestibular Apparatus can be suspected

Detailed Answer:
Dear Cynthiarn,

Thanks for your query.

Regarding the symptoms as mentioned in your post, kindly let us know about the following:
1. Any history of recent illness or injury/trauma to the back and legs?
2. Sensation of weakness in both legs can be due to poor neuro-muscular co-ordination secondary to systemic illness. Is there is significant past history of systemic disease like Diabetes, Hypertension, Thyroid disorder, etc. ?
3. Any recent history of Stress, improper nutrition & lack of sleep?
4. Habit of smoking or alcohol consumption?
5. History of prolonged intake of any medication?

If your answer to the above mentioned questions is "NO", then the symptoms can be attributed to:
1. Over stimulation or pathology in the Vestibular Apparatus in inner ear (it is associated with maintenance of body posture & balance) most probably Benign Paroxysmal Positional Vertigo: sensation of movement even when standing still, can be explained on the basis of it.
2. Inadequate hydration status & electrolyte imbalance of the body.
3. Dietary deficiencies of certain nutrients like Iron, Calcium, Vitamin D, Vitamin B12, Folic acid, etc. which help in blood formation & nerve conduction.
4. Entrapment of nerve fibers at the Lumbosacral region.

Though symptomatic relief can be obtained with intake of Vestibular sedatives like Betahistine preparations (to be taken only under the guidance of a Physician), the underlying cause needs to be treated.
Intake of nervigenic agents (like Vitamin B6, Vitamin B12, Folic acid) as well as multivitamin & multimineral supplements including iron, calcium & Vitamin D needs to be added in your diet.

If symptoms still persist, kindly consult an ENT Specialist & get a proper clinical examination done.
Investigations like estimation of blood pressure, blood sugar levels, serum electrolytes & vestibular function tests will be required to rule out any pathological cause for the symptoms.

There is no need to worry, you will be fine.
Till then, maintain adequate hydration & proper nutrition status and avoid stress.
And also take precautions of getting up from bed slowly & avoid sudden head movements.

Wishing you a Good Health.
Please let me know if I need to clarify further.
Take care.

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