I have this severe pain on my right hand side, about the waist area and towards my back.
It started gradually about 10 days ago, but now when I stand up from the chair, or move to the left or right, its excruciating and sometimes makes me scream out.
kidney stones feel like a localised blade slashing through you, almost a steely-cold pain and very intense but, as I said, localised and then it moves down you as it passes through the renal ducts into the urethra.
Sounds like a muscular pain. Renal colic pain tends to start in the back and radiates around to the groin. Your posture would make no difference with renal colic either.