Your symptoms are a sign that the herbs are taking action-- the die-off is chemicals from the dying worms as well as other toxins in the body being dislodged- which have attracted the worms there in the first place.
Make sure to get plenty of liquids throughout the day to help wash out these toxins through the bladder. A simple Colon Cleanse also would help. I like anything with Cascara Sagrada herb in it-- I take it at night before bed with a little water. It starts working in 8 hours or so.
I would do the parasite cleanse for no more than 30 or 60 days at a time.
You are on the road to progress, even if it doesnt' feel like it !