Hi.
Thanks for your query.
Noted the history and understood the concerns.
Since the pain started in the left leg, left testicle and slowly moving up but all on the same side, it is most likely to be due to the problem wither in the same side of spine or in the brain on the right side, the opposite one.
I would advise you the following in such a situation:
Get a clinical examination and evaluation by a
Neurologist.
MRI of the brain and the whole spine may help you to get a proper diagnosis.
Assisted by the tests of blood.
Also a test of spinal fluid can help a lot.
Get the
nerve tonics and multivitamins as these help in recovery.
Watch for the small trivial things like changes in bladder and bowel functions, the type of pains and pins and needles sensation.
Any instigating or enhancing factors and avoid these effectively.
Benign Intra-cranial
hypertension, raised sodium in the blood, brain and body also can cause the same problems. Hence get the serum electrolytes and other relevant tests.
A proper diagnosis alone can help for the plan of management as your tests in the past like
ultrasonography, TMT, ECG are all normal and may not be that much relevant.