What Causes Intermittent Shakiness And Nervousness?
Probable anxiety
Detailed Answer:
I read your question carefully and I understand your concern.
Judging by your information and the fact that you don't report any additional symptoms which could indicate any other cause I would say that these manifestations are most probably related to anxiety. Tremor is a common manifestation of anxiety.
Most of times there is no identifiable cause for anxiety, but at times there are causes like high thyroid function or electrolyte alterations. So some tests are necessary to search for them and treat them, simple blood tests such as thyroid hormone levels, electrolyte panel, blood glucose, liver and kidney function, blood count.
If no such cause is found then anti-anxiety medication is started when issue is persistent, usually with SSRI class antidepressants.
I remain at your disposal for other questions.