I too am a diabetic.
I don't think hypoglycemia can cause nerve numbness. The recognized symptoms are:
nervousness,
sweating,
intense hunger,
trembling,
weakness,
palpitations, and
often have trouble speaking.

The trembling and palpations are the opposite of numbness. So, your doctor may be correct about that. Certainly, if treatments used for hypoglycemia aren't alleviating the numbness, you need to return to the doctors.

It can be serious. It can be a symptom of several disorders, including an impending stroke. Please return to the doctor.