i understand your symptoms and your question. it may be peripheral neuropathy. i would like to know your age and whether you have diabetes. if you have any back pain radiating to the legs then it can be a spinal problem. i suppose you do not have back pain. the second possibility is hypothyroidism in which there can be such symptoms. if not checked then you need to check thyroid profile. you should get ssep (somatosensory evoked potential) and ncv (nerve conduction velocity) studies of both lower limbs. we will know the function of the nerves in the lower limb. you can get it done at any electrophysiology laboratory. you should get free t4 and tsh done (thyroid-stimulating hormone) to rule out thyroid problem. i suppose you would have done b12 levels before starting the injections. regarding medicines the dose that you are taking now is not adequate. i would suggest you tablet trigabantin 300 mg (gabapentin) twice a day after food and tablet pregabalin 75 mg at bedtime. consult your specialist doctor discuss with him or her and take the medicine with consent. you may feel little giddiness after these medicines but that will settle in three to four days time. for further information consult a neurologist online --> <link>
what test should i do to know the reason for tingling sensation?