OK so leave the question blank and discuss it with the AME. BE honest - a bad headache, period. Your AME will then tell you what to put on the form
Personally I agree with 421Dog - but I am not an AME. Choosing a 'nice' AME is as important as when choosing any doctor ! Most of us find it is a nice chat with a few tests, and AMEs really dont want to dig through records with an honest pilot who has benign issues