I had an experience a couple years ago where i felt a warmth behind my neck and all of the sudden something exploded of energetic or neurological source and it ran through my body. i need to understand if what this is. cause it affected health greatl?

More details are needed. We don't have enough information to comment. Please provide more details

It is not feasible to provide a meaningful opinion without additional history, physical examination and may be some tests. What you described suggests a pinched nerve and if the symptoms have abated you may ignore it. Regular aerobic exercise will help improve the issue by raising core body temperature and improving muscle health. If symptoms recur, it would be prudent to see a doctor.