Hello! Thank you for asking on HCM! I understand your concern. I would like to explain that the metallic type taste can be associated to different disorders like : vitamin deficiency, oral infection, hormonal imbalance or a multiple sclerosis relapse. The sharp pain in your upper spine irradiating to the left shoulder can be associated to a pinched nerve or a radiculopathy originating in your cervical column. I recommend you to consult with your neurologist for a careful physical examination and compare with your previous situation. A brain and cervical spine MRI is necessary to exclude a possible relapse. In this case you would need treatment with steroids for a short period, besides copaxone. Hope to have been helpful! Greetings! Dr. Aida