Questions on involuntary movements in sitting meditation

https://www.reddit.com/r/Meditation/comments/bz69mf/harmonic_involuntary_body_movements/

Harmonic involuntary body movements

I recently completed a 10-day Vipassana course, and had many mind-boggling experiences, and left with some answers, but even more questions. Posting here in case anyone has any directions to offer, esp since the teacher freaked out and asked me to stop meditating, alleging I had a mental illnesses (no track record of that) and threatened to throw me out.

Here it goes: On day 7/8, I had two experiences, which gradually kept growing in intensity. I have to give a disclaimer here that I am an intense person and like to give my best, so was doing that here while meditating too, but not by exerting force. The first experience was slightly intimidating, as my fists clenched and my body was involuntarily shaking after I had reached a stage of "flow" in scanning my body. I was aware, equanimous, and patient in observation as my body convulsed and the experience lasted around 45 mins. I didn't freak out because I was completely present and aware, and also because I'd had harmonic movements in my first ever meditation experience in life 10 years back for Osho's NadaBrahma meditation (arms swayed gently to the music, and body preemptively sensed when music was about to end). I thought it was interesting, but didn't give much heed to it (may have meditated in 15 sittings in last 10 years). Back too the current experience - after about 45 mins of shaking and some involuntary crying, my body relaxed and I felt really calm.

The next day I was getting deeper in my focus and in the morning session, my arms, neck and also torso got a life of their own. It was similarly smooth and harmonic as my first ever meditation experience, and unlike the violent experience on the previous day. Again, I didn't intervene but the teacher sent the coordinator to ask me to relax but I was already really relaxed. Nevertheless, he forced me to go out for a walk - I was surprised that my hands were still moving even as I opened my eyes and walked out. The teacher saw me and threatened me to stop though all these motions were involuntary. Anyhow, since this was still in my control, I force-stopped myself and it felt very coercive to do so.

In the afternoon, I didn't allow my hands, neck, or torso to start swaying but again went into a very deep focus mode. My body and mind became very relaxed and I was barely taking a breath every 15 seconds. The awareness increased dramatically and I could feel my heartbeat even in my butt and legs and sensed the internal sounds of my body very distinctly. Then all of a sudden my breath went into the involuntary harmonic mode, and was perfectly in sync with my heartbeat - it was like I was listening to music effortlessly. My back straightened and remained like that and my neck was upright too. It was so effortless that I didn't want to offer any resistance. Along with the movements, there were very strong sensations on my right ear, nostril and especially middle of the forehead and I could feel energy flow without any pain or discomfort. I was still aware of my body and the processes though. Unfortunately, the teacher had threatened to throw me out the previous day if I didn't stop meditating every hour, and it was already 2.5 hours. I forced myself to get up after the 2.5-hour break, and slowly took the involuntary breaths back in my control and started coming back little by little. Eventually when I went outside for a break, I was aware but my head was just not in the moment - I felt like sitting down to meditate again but had to abstain because of the situation. I was also getting slightly freaked out by this time because the teacher had told me the previous day that I would most likely end up in a hole that no one would be able to get me out of. The sensations on my nostril and middle-forehead were strong throughout but my consciousness was just not coming out of the meditative mindset. I eventually returned back to my complete sense only at around 1230am after getting into it at 230pm, but was really panicked by the end of it thinking that I was going cuckoo.

I stopped meditating for 2 days after that and writing this post today. I've always considered myself rational and don't even believe in multiple lives or such, pushing my beliefs to only as much as I've experienced myself. Looking back, I'm tempted to think that I self-induced a hypnotic state, or that control from a specific part of my brain was bypassed with deep concentration, but wondering if anyone else has had any similar experiences or could help me come to terms with this!

Thanks in advance.

response in general

Involuntary body shaking in sitting meditation can be perfectly normal. The Buddha talks about it in this sutta SN 54.7:
http://lucid24.org/sn/sn54/sn54-007/index.html
Shaking and vibration can range from mild, like nose or mouth twitching, to strong and even violent shaking, but with persistent correct meditation done over a long period of time, the energy will smooth out and eventually shaking will disappear. Doing yoga, accupressure, other healing health modalities can accelerate the smoothing of the energy flow.

Naturally, the more violent the shaking, the more scary it looks to outside observers, and the more worried they are. Probably most assistant teachers don't have personal experience with shaking and vibration, and are not taught how to deal with the situation.

But with that said, meditation can trigger serious mental health issues, with or without body shaking, and even for people who've been meditating a long time and getting the expected positive results. So it's reasonable for assistant teachers, and even expert meditation teachers with tons of experience, to take precautions to err on the side of safety. If in any doubt, check with qualified professionals. Safety first.

why i don't feel the strong vibrations anymore?

https://www.reddit.com/r/Meditation/comments/clhgh4/why_i_dont_feel_the_strong_vibrations_anymore/ 

when i first started meditating i felt strong vibrations in my body but after 20 days later i don't feel the strong vibrations anymore? now it's so week. anyone feels like me?
sorry for my bad English.

The body condition is always changing. If you meditate long enough (years), you'll likely experience all kinds of strange bodily phenomena. It's normal. In general, body shaking and vibrations are going to get smoother and eventually disappear, the body will get softer, more pliable, feeling lighter. The feeling of mass, tightness, and vibrations generally are the subtle energy channels being blocked, and the energy is bouncing back. The more you meditate, the channels are going to open up wider, vibrations will dampen and gradually disappear. Another way vibrations might be decreasing is your overall energy declined, from doing energy draining activities. Sex, undersleeping, partying, gambling, etc. But if someone is celibate, meditates frequently, then the body is going to get softer, lighter, mind gets sharper, clearer, vibrations will smooth out and energy channels widen.