New onset myoclonus in person with hx of anxiety

Hello. I'm looking for some advice regarding new onset myoclonus. About 2 to 3 weeks ago, i started experiencing myoclonic jerks several times each day, almost invariably unilateral and involving most often the proximal muscles and trunk (e.g., hip adduction, lateral flexion of spine). Over this time, they have increased in frequency as I continue to worry, and they now occur in virtually any muscle in my body, though more often in arms and fingers, and I'd say about 2/3rds occur on the left side of the body.
1. Not hypnagogic; occur usually during day
2. Usually occur at rest, though occasional jerk occurs during contraction. Sometimes > 10 per hour while at other times 1 or 2. For the most part, the contractions are small and not obvious to other people (e.g., brief, small forearm pronation), though there are occasional large jerks (e.g., spinal lateral flexion or strong hip adduction) as well.
3. 25 y/o male. No hx of medical problems, smoking, drugs, coffee/alcohol, or trauma
4. Hx of anxiety disorders with multiple possible somatization complaints (e.g., IBS).
My questions:
I have arranged to have blood work done (TSH, electrolytes, AST, CBC, creatine, glucose, etc.), but am still interested in whether anxiety is a common cause of abrupt onset multifocal myoclonus. Being an anxious type, I am concerned about worst case scenarios like brain masses, especially given the rapid onset. That said, I don't have any other focal neurological deficits that I can see (I'm a medical student...I pass a basic screening neuro exam), so I'm not sure how often myoclonus occurs as the presenting symptom of a serious disease. Could this just be another manifestation of anxiety, even though it's never happened before.

I'd appreciate any general advice/info and a comment on how likely anxiety is as a cause for myoclonus of the described nature. If it is unlikely, what are the chances this could be a sign of a very serious disease?

Thanks!

[Caryopteris]

I had a boss who had this.  She saw the doctor for blood work and it was always normal.  She was classic for anxiety, but also smoked and did not exercise much.  When I still worked there, she was still looking for answers.  I think maybe her doctor was afraid it would make her mad if he said it could be anxiety.  She was hoping it was and she was trying to exercise more.  

[Caryopteris]

I always get an eye twitch when I'm situationally anxious.