I used to get migraine headaches and it tended to be related to food, sometimes chocolate or cheese, and I used to feel very sick with it. Do you get the pain behind one eye? or bright flashes in the corner of your eye? Or feel it worsen if you're hungry? If it's migraine usually you need a painkiller with an anti-emetic, Migraleve from the pharmacy or something stronger from the GP, because if you feel sick your stomach doesn't absorb as well as it usually does and so the standard painkiller just sits there and is less effective than normal.