Basically anything can happen when you have die-off, headaches, fever, cough, dizziness, etc. When the parasites die or struggle with their last breaths, they can cause such things to happen.
I would suggest that you continue with the protocol.
Your parasitic load sounds to be quite big at the moment. So the die-off can be severe at the start. But this seems to be working and you are finally starting to kill them.
So, I think you should go with it but at the same time listen to your own body and go at a pace, that you can handle. Don't raise the salt and c-vitamin amounts, until you are ok with the current state.
Remember to drink more water too, as they suggest, so the parasitic toxins get flushed away.