Brief Answer:
No, I do not consider it normal

Detailed Answer:
Hello ma'am and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. There can be numerous causes for such a presentation, but no it is not considered normal. Although it is difficult for me to pin point a particular cause, which can only be done by an elaborate medical check up including different fields of medicine, I can help by listing some of the most common causes that come to my mind.

They are:

+Neurological abnormalities: Some major nerves help control that movement, and weakness or pathology can cause weakness resulting in a reduced ability to control your chewing or mastication
+Infections
+Weakness: Can be caused by different conditions (e.g. anaemia, hypoglycemia, blood pressure fluctuations, etc.)
+Anxiety, stress, or depression
+Brain related abnormalities
and many others.

So as the presentation is bilateral I think we can rule out a nerve abnormality, as it presents mostly unilaterally (one-sided). But please do consult your doctor for a more elaborate evaluation, as this could be an indication of some underlying condition requiring medical attention.

Please also do not hesitate to write back to me for any further clarifications, I am always here to help.

Best wishes.

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