Still going, but it's becoming more just stubbornness

Day 7, and no longer doing so great. Yesterday the heartburn and occasional nausea I'd been feeling got very bad, and by the end of the night I was feverish and shaky and headachy and felt pretty awful. I stuck to my guns and went to bed. This morning I feel better, no longer feverish, and while my stomach feels tender (as though I'd vomited) I'm not nauseous. I do feel weak and achy as though I had the flu, though. Just going up the stairs once is exhausting and leaves me out of breath.

I'm treating this as a crisis, or a detox moment, and I'm going to keep going until Friday as planned, but I could use some encouragement. Has anyone else felt this way?