Unusual headache - suggestions as to cause?

  I can sling lobster traps 1000's of pounds and no headache.

   But if I am cutting up meat or veggies on the kitchen counter,  if I look and angle my head naturally looking at what I am doing, no headache, but if I let my head drop all the way down until my chin is almost to my chest and be looking upward,  In two to three minutes of doing that I get a massive headache.

  No stress or straining... just the position.

[Eddie1994]

It seems to suggest that maybe two factors could be at work: 1) pressure on the spinal cord by a disk or; 2) arterial blood pressure.  A Neurologist could help you solve this problem and make sure its not something more serious.

[Dr Santos]

Hi,
How are you? I agree with the above post and you may need additional diagnostic tests also after evaluation of your neurologist. These include imaging studies to determine if there is aberration with anatomy or pressure  present.  Try to avoid this position to prevent recurrences or take preventive medication if there is a need of this specific position. Take care and do keep us posted.