Did the colonic do anything to help? This is one reason I’d avoid them. Didn’t they give you any kind of electrolyte supplement or recommend drinking something with magnesium, potassium and calcium and sodium? You might already be low on sodium, since you need to add salt to your food to get any without processed junk in your diet. If you’re eating low-carb, you’re not able to hold onto much water or electrolytes (this is what people lose at the start of Atkins), so you need to replace them regularly.