Lots of ladies put on during * week. It's quite normal so just carry on Food Optimising and it'll come back off. It's best to look at your losses over a month rather than on a weekly basis for that reason.
I definitely do, think it's down to water retention mostly. I weighed at home last week and was down 2lbs but by the time it got round to WI I was only down half down to * (I hope - teach me to sneak peeks during the week!)