Thank you very much for posting this question in HCM
Let me tell you that a given medical problem can be due to various causes and the primary aim of the attending doctor is to find out the exact cause and deal with it accordingly rather than simple assumption in the modern era of medicine.
back your question, the causes of twitching are many. The presence and absence of other neurological symptoms like weakness of hands, legs, numbness
any where and wasting of muscles and pain in muscles etc will help us further narrow down the possibility. How ever, you have not told us about the presence or absence of these symptoms in you. None the less, as you have not told, it is probably absent in your case. Twitching can happen because of local nerve problem, nerve root
problem or motor neuron disease
and also it can happen normally. As you probably don't have the warning symptoms as i have listed above you may follow either of the two path an resolve this issue
1. As it is highly unlikely that you have a serious neurological problem, you can observe for about 4 weeks time. If you develop an new symptom then go to a neurophysician who will examine you and approach the way i listed above.
2. If you are still worried, immediately visit a neurophysician and get examined and then plan for further tests in order to determine the exact cause and deal accordingly
Hope this clarifies