Did half of SOP from GT onwards (wanted to practice it slowly, also, not a convenient time to take incense and to do 供香). Felt warmth and numbness on my back again. The numbness was strong when I was chanting OMPH using 金刚念诵法 and while doing pranic breathing. Today, I managed to do GYFM for slightly longer, about 35 minutes. Back was still aching, but I tried to persist longer. During GYFM, I felt something pull me behind, such that for quite a while, my balancing point was at the edge of my butt. When I tried to sit properly, I get that pull again. At one point, while sitting in that unbalanced position, I felt a strong and warm pressure at both side of my back, slightly beneath the shoulder blade. It was a very distinct and warm feeling.

I think I also felt my 3rd eye chakra, but it was just a mild tightness around my forehead, somewhere in between my brows. There was no throbbing, but the tightness lasted some 10 minutes or so.