Day 3 Pre Op feeling BLAHH

Not going to do a big update, been crook. I have had diarrhea for about 24 hours now. Just really wearing me out. I do suffer from irritable bowel syndrome, but that is usual brought on by too much fat or gluten. I am having my 2 tablespoons of Benefiber a day. Was thinking maybe I have just picked up a bug, but my kids are not sick!
My intake for the day is:
6 x optifast products
2 tablespoons Benefibre
2 x vitimin D tablets
1 x Ferro-Grad C (Iron)
1 x Allopurinol (for gout)
1 x Metforman (Diabetes)
1 x sugarless C
4 x 500ml water


I actually only had 5 optifast last night and  couldn't finish my last water  as I was feeling nauseated. Still have to have 1 more optifast to go today its been a struggle with feeling so yuck. Major headache too.
daughters making up my last optifast shake for the day for me, and I'm trying to polish off this 500 ml water. Then only 500ml to go. About to go to bed early tonight, no energy today.

So has any one else suffered with diarrhea in the first week? Or is it just me and my stuffed up body?