Oh yeah, I'd say this is normal. Someone who had taken the anti-viral before also posted about strong detox effects as the herbs were killing off the viruses. Do a search and see if you can find it.
I'm having an awful time with the liver cleanse. Lots of symptoms and discomfort, but I'm gritting my teeth and hanging on because I know RG's herbs are doing something good for my liver. Same with you. Stick it out! :)