Annicca ,i can only speak from my own experience & i do not tend to like to label things ,i posed the last question to you because ...as i said in my earlier post ( and i should preface this by saying i was a dance major and these were the 1980's before google
) so from years of dance practice a natural progression lead to yoga & then meditation ..after i corrected the issue in 4 sittings i had a profound experience ,during my meditation i got hot all over ,sweated,shaking ,felt every part of my body ( painfully aware) then crying (joyful) i had no idea what was going on & i tried to breathe through it all after that happened ,people i spoke to had different opinions some said wow you were so tense your body was just letting go ..others said it was negative energy being released ...proper chakra alignment ..demons leaving me ...my uncle who lived in australia at the time & considered (new age,as he practiced buddhism and meditation ) said i experienced kundalini.
some would say in vipassana to "breakthrough" the shaking would be progress ,some would say different . my opinion is to trust that what is happening (shaking or not shaking ) is a natural process unto you .be aware as the sensations happen ,say to your self i am shaking ..let it go.... i am hot ..let it go ..etc this is the mind body connection ,again you worry have you regressed .be mindful in your practice whatever practice it is ..watch it float past do not cling to it .this is the best answer i can give .
keeping the mind in perfect tranquility and free from any attachment to appearances."
"So I say to you -
This is how to contemplate our conditioned existence in this fleeting world:"
"Like a tiny drop of dew, or a bubble floating in a stream;
Like a flash of lightning in a summer cloud,
Or a flickering lamp, an illusion, a phantom, or a dream."
"So is all conditioned existence to be seen."
Thus spoke Buddha.