bad headache - detox?

Hi Shelley,
I wrote you last week about some herbs that my naturopath prescribed. I am taking bupleurum, livit 2, sweetish bitters, and bile salts to help with a low functioning gallbladder. I had just a short period of increased nausea, but then started to notice some small improvements. Now, after taking the herbs for 13 days, I have had a killer headache for the past 3 days. I try not to take too much for it, but even advil doesn't put a dent in it. I've tried Epsom Salt baths, neck massage, and enemas, and nothing helps. Do you think that this could be a detox headache? Are the herbs I am taking ones that would cause a detox reaction? My nausea was getting better, but with the bad head pain, it triggers nausea. I can wait it out if it is just detoxing, but concerned it may be more than that. How long would this usually last?