Yes, these are very common symptoms during detoxification. Headaches are especially experienced when coming off of stimulants such as coffee, Ceylon / black tea and green tea. Over many years of consuming these stimulants as well as mostly cooked / dry / dehydrated foods (potato crisps) the body becomes severely dehydrated and dependent on them to maintain proper circulation to the brain. Thus, once it has been suddenly removed from the diet it results in tension headaches. In this case hydration is very important and an emphasis should be placed on fruit juices and citrus juices – daily lemon juice is essential!
Nausea is typically a result of a thinned stomach / intestinal lining and/or poor liver function or congestion of the liver. In time this will change but while these adverse symptoms are being experienced the stomach and liver function should be supported with appropriate foods, superfoods, herbs and supplements recommended for your personal case by your Natural Medicine Doctor.
In rare cases of constant extreme nausea, it can be a complication of severe kidney disease or cancer in which case your practitioner / Doctor must be consulted.