Thank you for sharing what you witnessed in Basel. I certainly am one of those whose meditations are quite physical, i.e. I tremble, shake and 'rattle' quite a lot. My first Blessing of the Centers meditation resulted in the most violent purging (the bowl was my friend for quite a few hours from both vantage points) a few hours later because I had envisioned a fireman's hosepipe blasting my 3rd center open and clean!!!! Nuts? Maybe... or maybe not. Since then, my energy flows upwards unobstructed, however.
Fortunately, I am not new to meditation so I am not discouraged by physical reactions but as I worked to get deeper into Dr Joe's meditations, I became aware that focusing on the movements was also a way of not detaching from my body. So, slowly, I began to allow these movements to express without my examination of them and the only thing I look at now is the energy moving up and out of my body.
I love doing the breathing part of the meditations because as DJ explains, it moves thoughts/emotions/mind OUT of the body in preparation for moving the mind out of the body. He speaks of thoughts in the body as almost obstacles to becoming 'nothingness'. (I know, it can all begin to sound so whoo hoo BUT if one takes it one step at a time, the Concept becomes an Experience and it makes perfect sense all around).
My first experiences with this breath - even though I have practiced the Kundalini Yoga breath of fire for decades - was challenging. I thought I would die from not being able to expand my lungs and hold the breath. It was as if I had never breathed in my life. Quite quickly, however, I found a natural rhythm and I am now able to breathe in an up and hold quite seamlessly and by the time I hit the meditation, I am totally open and relaxed.
Like you, however, I have had a dramatic incident happen - it was just last week: I woke up feeling out of sorts and unwilling to do the work. Despite that, I sat down and started to breathe. Over eagerly, I squeezed everything with such force (I was angry at the blockage I felt was in me) that something happened: first, I felt a surge in my pituitary gland area and after, had a tremendously powerful meditation and experience that left me feeling vulnerable and open to let myself cry (I don't do that very often).
Despite this vulnerability, in my waking life I kept my awareness on my state and chased the thoughts behind the feeling - I wanted to discover what the thought behind the "offeness" was, specifically. Not long after, I found it! What a revelation. However, as I sat down for lunch with my friends (an hour later) they watched my eye fill with blood and by the time I looked at myself, I was surprised.
Did I panic? NO. I stopped myself from going into a state of fear and to question too much. Since then, I have just adjusted the intensity of my 'holding' and of the squeezing and now the effect of the breathing is just as wonderful and my meditations, just as powerful.
I would not worry too much about it. Breathe more gently; squeeze more gently and ASK FOR GUIDANCE... You will receive it from within.
P.S. By the way, the eye is clearing really well. No vision disturbance and doctors confirmed that it was a harmless situation. Point is: take it within your stride. Take it easy and build up. You may be holding the breath too long.