I'm not sure but I'd try not & constantly weigh yourself at home and just stick to the once a week LL weigh in. That's what I was told as it can effect your mood/actions if you get disheartened if you think you've gained (as you've done) lol x
Answer to that is to weigh yourself once a day at the most at the same time and in the same clothes. Not weighing would be even better - but hey i am being realistic - I do it myself a few times a week too.
Top answer your question . Your body could have become dehydrated overnight and be holding on to some water. it will make its way out of your body during the day. I think this is the likely reason.
Funny that as out of curiousity i weighed myself 30 mins later with my pj's on (was naked first time) and weight was down ha. I'm not that bothered as know it fluctuates and like to weigh myself midweek but was just curious how it happened overnight lol. Supposed to have 2nd weigh-in Saturday morning but i can't make it so got to wait until Mondays class. Going to weigh myself Saturday morning to see how i'm getting on. Think i'm looking at 2lbs judging by this morning which is good enough for me x