Since a few days I have a trouble when I sit.
When I sit down, and I'm straight, I feel the bones of the lower basin (between the buttocks and thighs) undergo pressure, what bothers me and prevents me from concentrating.
I sit like I always did, I tried to change my posture, but nothing changes.
I had this one time but don't remember how it vanished.
Does someone have an advice, and/or can explain what's happening?