Yin is slower than anything else on the timetable, and that catches people out. You will hold four or five poses for up to five minutes each, propped with bolsters and blocks.
It should not hurt
You are looking for a moderate, dull stretch, not a sharp one. If it sharpens, come out a little.
The hard part is the stillness
Most students find minute three uncomfortable for the mind rather than the body. That is the practice.
