Actually the entire month after all my treatments was the worse, as I had not found OCF and did not realize just how BAD even though the burning and poisoning stop. Yeah the doctors' mentioned it, but did not stress it enough.
So be prepared and not discouraged when it happens. However, let me add that you cannot imagine how GOOD it can get a year later. Hang in there and read some survivor posts especially the anniversaries. You both have reached an important milestone, sort of like the 20 mile mark in the marathon, where everything hurts but you can finish. ( I used to laugh when my medical team would use marathon analogies as they had never even run one, while I had done four)