Hi, yes i do,
Internal tremors were assumed to be invisible but some more recent research done in 2016 or 2017 apparently suggested internal tremors still produce movement but it's just too slight to see with the naked eye.
I actually think there might be a few people who live with an internal tremor who've already worked that out, oh and that sometime you can get an internal tremor to actually be seen.
I accidentally discovered my invisible tremor could become visible almost a decade ago now, it sounds a bit weird lol but afterwards i was told by a doctor that what i did was a very old school medical test, no clue if that's true or not though....so i was cleaning the top of a bedside table and to protect my son's school raffle ticket that was in the way, i gently placed the ticket between my lips and surprisingly the raffle ticked started moving to the exact same beat as my invisible tremor.
I've also only recently noticed the if i'm wearing a bracelet that has charms that dangle and jiggle about, those charms on my bracelet will actually be moving even when my body is supported so there might be something in that one too...?
If you look this up you will likely come across the 3 causes that are more commonly mentioned, all but 1 is serious and it's the 1 that's not serious that is the most common one diagnosed. 1-Essential tremor (ET), 2- Multiple Sclerosis (MS) 3 - Parkinson's Disease (PD)
You will also find tremors, external as well as internal tremors, also mentioned in mental health conditions like anxiety, but its hard to tell what came first considering an invisible tremor can cause anxiety and anxiety meds can cause it. I believe there are even things like vitamin deficiencies and hormonal issue that can this type of sensation too.
Hope that helps........JJ
PS. What does your doctor believe is going on?