First, let me say I don't have true wisdom, but I'm willing to share my own experience with you. I'm sure that someone with really true wisdom will jump in later on.
Your true weight is the one from early morning. You go to the bathroom and then you weigh yourself before eating or drinking anything. After you eat, your weight will change! I usually weigh 5 lbs more at night than in the morning. Don't worry, it will go down the next morning.
A few things to consider:
Have you lost inches? Nobody knows how much you weigh; it is just a number on the scale. But they will notice how much better you look. Sometimes you just loose inches because the weight is rearranging through your body. Also, one and a half weeks is not enough time to worry. Sometimes your body takes time to get used to the loss and you are stuck in a number for a while and then your loss resumes.
I have been stuck on 140 for a while; I know I could do better if I'd cut a few LC extras. Think about any extras that may be stalling you: cheese, sodium, artificial sweetners, LC sodas and products in general.
Increase the amount of water you take. Also, are you taking the supplements?
Keep in mind that you may retain more water around TOM, too.
Hope it helps a little.