Have throbbing below right rib, comes and goes, had scan on kidneys all okay so kidney stones ruled out. Hot water bottle seems to help?

No short answer. I would guess you have strained the right upper abdominal muscles. The scan should have noticed if you had gall stones. It is easy to strain the upper abdominal muscles turning over in bed wrong, losing our balance & trying to keep from falling or being hit in the side by a door when the wind catches it. As you found heat will help a lot, use it for 15+ minutes 3-4 times a day when you can.