Thank you for all the information.
The burning sensation can be due to pressure on nerve.
Increase in pressure during certain posture can precipitate the sensation
This can occur in the spine & radiate towards the front side.
Kidney or urinary causes like infection or stone are other possibilities.
Your urine test result was good.
You can have an ultrasound or scan.
I would suggest to discuss those points with your doctor.
I hope this information helps.
If there’s anything else I can do, please let me know.
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