I can't say specifically for you but I know when I've eaten too much fat earlier in the day and then eat something really sugary I'll get headache like symptoms.
flouride causes heads to hurts :)
I would bet without knowing anything else, that it is you are dehydrated... How much water do you drink per day, are you fully raw? If eating any cooked, you need roughly 2 liters just for that meal... If you are eating dates, something I read on here that I agree with is you need a glass of water per 3 dates just to hydrate the dates... We have much higher water requirements than many realize in my opinion, due to many, many factors.
That doesn't happen to me, luckily! Since you said "anytime I eat sugar, especially fruit..." you are getting sugar from sources other than fruit, right? So, you're eating processed foods? I would cut that out before blaming fruit for headaches.
I was asking for m friend and she is still eating cooked food and processed food. Thanks for the feed back guys! I will let her know what you guys think and report back if anything helps.
I'm actually really interested because I've also been getting headaches. This is my first week high carb and raw till 4, so I am wondering if headaches are normal at the get go? They are almost constant since I have started.