It's Lucia again. Forgot about addressing how to find triggers. You're right about keeping a journal. That's your best bet as everyone is different. My triggers will not necessarily be your triggers, etc. Besides my food trigger list, here are some of my triggers to keep in mind to see if they affect you:
loud noises and/or music
bright lights esp. flashing
weather and altitude changes
too much exercise, too little exercise
arthritis in the neck, jaw (TMJ)
head injuries - concussions, etc.
crying, sudden alarm or prolonged anxiety
scarey movies or really intense movies
emotional conflicts w/people, friends, anger, fear, tension stress is a big one
colds, sinus infections
And you'll probably discover some of your own as you journa. Also one or two triggers won't necessarly set one off. Sometimes it takes three or more. Depends on how well I've been doing staying away from my food triggers. Again, hope this helps.