to be perfectly honest with you, on week 3 we had friends over and went on a camping trip, and very unplanned i ended up eating and drinking alot. and gained 9lb!
I got straight back on it the week after and lost the 9lb plus a further 4lbs. so to be honest hun, you will either gain or stay the same. and then u have a choice to make, either get over it and carry on or give up. i'm glad i opted for the carry on option because i've done Ok since then. (had a couple of hiccups) but nothing too damaging. you have to take each day as it comes and try your hardest.
what exactly have you cheated with?