How you will feel during die off is all about how healthy you are at the moment. Of course, it depends as well of the dosage and the potency of the herbs you are gonna use. Can you please tell me which herbs you're planning to take?
Die off can really be hard on the body, sometimes it can be life threatening. I've been there, when litterally hundreds of dead parasites were coming out of me daily. I was taking several high enemas daily to make sure everything was going out fast. But back then I was really at death's door, one could say. Activated charcoal helped. Several daily coffee enemas too. I had to juice fast several monthes in order to gain my health back. Don't rush the process, you better take it slow.