Hi, Welcome to Just Answer!
I am an American Board Certified Neurologist (studied & worked in USA) with a vast neurology clinical practice experience. I am familiar with the condition that you have described and can help you with your questions/concerns.
There are myriad causes for muscle twitching and based on the history you provided that it is of recent onset and no muscle weakness then ALS is unlikely!
Some common causes for muscle twitchings include;
1) Thyroid gland dysfunction:
2) Electrolyte abnormalities:
3) Medication side effects:
4) Excessive caffeine intake:
For thyroid dysfunction & electrolyte abnormalities a blood test for TSH & electrolytes will resolve the issue.
I assume you are not on any medications now. If ‘yes' and if they were started recently then it is worth holding them for few days & see what happens(not all meds can be stopped abruptly; some of them needs to be gradually tapered off).
If excessive caffeine intake is there then reduction can help.
You have not mentioned any stress/anxiety etc, so that is a less likely possibility but if you feel these conditions may exist then treating them will help you with the twitchings too. The treatment consists of counseling/therapy, medications (like Tab Buspar, Xanax) to reduce stress etc.
Benign fasciculations as the name implies are benign in nature. But it is a rule out diagnosis, means we need to rule out other possibilities before considering this as a possibility.
ALS is unlikely with your presentation. However if the twitching do not get better, and all above investigations look ok then you need to see a clinic-neurologist to undergo a clinical examination and also an EMG (needle test). This test is highly useful to study the muscles and will provide us more insight into your condition. This test will help in ruling out ALS as well, and again ALS is unlikely possibility in your case, but these are the investigations you need with your presentation.
Sometimes symptoms come & go without any consequences, hopefully that is all you have. All the Best!
These are my opinions & recommendations based on the details provided, and if you are seeking a more elaborative discussion or have additional concerns then please ask any number of questions until you clarify all your doubts.