Palpitations could be caused by electrolyte imbalance, potassium is the most common deficit. Use more salt and eat foods rich in potassium and magnesium to see if this helps. Oranges, OJ, bananas, kale liver, oysters, potatoes, sweet potatoes, salt your food, etc.
Beginning primal people cut out certain foods that may have been their source for what they're missing now. I'd track your food on a site like http://www.cronometer.com to see if you're low in anything and go from there.