<s>[INST] i sometimes have these out of blue spells where i feel weird or lightheaded sweaty nervous. then within a minute or two have to have a large hard bowel movement? is this related to vagal nerve? or could it be damage to nerves due to terrible neck thorasic lumbar problems? [/INST] Hello! Welcome and thank you for asking on Chat Doctor! I passed carefully through your question and would explain that your symptoms seem to be related to an autonomic nervous system dysfunction (legal nerve). In my opinion your symptoms are not related to any nerve damage in the spine. But, I would recommend consulting with your attending physician and performing some tests: - a Head Up Tilt test for orthostatic hypotension- complete blood count for anemia-thyroid hormone levels for thyroid gland dysfunction- blood electrolytes. Hope to have been helpful! Kind regards,  </s>