I know this is probably a little late now, but there's something my dad taught me which always seems to help. Calmly sit down and think about your headache. Don't think of the pain, just examine every bit of it - think carefully about where in your head it is. I know it sounds weird but it's always worked for me. It does take a bit of getting used to. And it's definitely a mind over matter thing. If you sit there thinking "this is never going to work" then it won't. And it's very important that you don't just lapse back into thinking "ouch" - you have to be as objective as you can.