i am familiar with the symptons you describe. not to scare you, but for me it has been a warning for things not going like they should. while i havent done a Liver Flush yet i can understand what above posters are saying.
and my experience with Liver Cleansing herbs is, that the suggested cycle indeed is FIRST to flush the liver and then start on some detoxing herb or whatever.
everybody is different though, so if you feel comfortable doing it the other way around go ahead. good luck