Hello and welcome.
It is hard to answer your question, because without first checking with your doctor, to rule out a physical issue...
...and without knowing your history with anxiety...it impossible to say what the origin of your twitch/jerk.
Anxiety can certainly be to blame...so if you have had a history of anxiety and related symptoms...and have had a recent clean bill of health through a medical screening...than you can probably safely assume this is what you are experiencing...
...and continued use of coping skills and anxiety management will be your best course of action.;)
Wishing you the best!
"Courage is not the abscence of fear, it is feeling afraid and doing it anyway!"
"Worrying does not empty tomorrow of its troubles...it empties today of its strength."
Corrie Ten Boom
Panic Syndrome recovery due to CBT