First day on Wellbutrin; will this go away?

Most likely, this side effect will go away once your body gets used to it. Speaking of coffee, it increases anxiety, if you have several cups a day. I would take wellbutrin with food, so it doesn't bother your stomach. As far as foods effect on absorption rate, it won't make a big difference. Don't eat grapefruit though, as it can interfere with Wellbutrin's effectiveness.