I don't remember having a headache but that doesn't mean it couldn't be from the Lamictal.
Here's a site you might check out, rxlist.com. Look up Lamictal and you should access a whole page with charts listing side-effects in order of prominence. I just checked it out, and headache is a side-effect in 29% of people.
I will say that when I got up to 100 mg., I had clumsiness and lots of bruising but they went away within a few weeks and so long as I don't go over 100 mg. on a regular basis, I'm fine.
I don't know what it is these days with taking us off antidepressants. Think there's a new theory out there that they make things worse. Maybe so, but with Prozac, I'm depressed. Sadly, my body hasn't caught up with this new theory, so till it does, I'm staying on Prozac.
Best wishes.