For me I noticed it depends on the trigger. All of my trigger foods are alcohol, and none of them are the same....Shiner Bock Beer for whatever reason is the quickest...literally get my aura from smelling it and a head pain within 30 min...doesn't go away for 24-48 hrs. Vodka causes nothing (weird)...red wine is hit or miss...cheap ones I won't get the head pain till the next day even with more than 1 glass but it doesn't last long. Gin will give me head pain for about 24 hrs.
That's the head pain portion, I usually also feel like BLAH for about 3-4 days until it is all out of my system with lots of water drinking even if it was only one drink (or smell in the case of shiner). The more sensitive my body is to the type the longer I am in the migraine even if it is the post head pain phase.
I have noticed that if something throws my gut off balance (preservatives, MSG, really high sodium, dairy, American Bread (very specific to American not European)) I will be more susceptible to get a migraine but I don't think of them as a trigger. It is hit or miss as to whether I am currently eating right and just a one off or if I am in a week binge of bad unhealthy food I just feel all over yuck and then I get whacked with Aura and migraine.