They can be moving arms, legs or torso perfectly normally for days.
Then after only a slight movement the pain starts.
When they are lucky they have their pain killers to hand; if not, the pain will be too great to move, so they stay very still and wait for the pain to subside a little, then they get and take their pills.
Even after taking their pain killers many remark they feel as if they have been kicked in the stomach.
They might go a day or even weeks before the pain starts again.
They risk getting the pain every time they do an everyday task and it may take the stone weeks or months to be ejected.