Speaking of scale accuracy...
I've been using a digital scale at work for my weekly weigh-ins. I've discovered that my weight can vary by as much as 10 pounds depending on how I stand on the scale. If I lean forward and put my weight more on my toes (as I might do when peering down to read my weight) I tend to weigh less. I'm human enough to always do this now that I've discovered the trick, so my loss week to week now is probably accurate but I don't know how I was standing on my first fateful weigh in. I bet I was back on my heels for that one. I was also possibly retaining water due to TOM so that initial weight might have been 10 or so pounds on the high side.
Still, I'm leaving my ticker - that scary first weight was one of my key motivators to start this journey and my early weightloss success gave me the strength to keep going. What matters is how I feel (healthier! more energetic!) and not the actual numbers. And now that I'm always "on my toes" for my weigh-ins I think my numbers are accurate in relation to themselves if not reality.
"Vision without action is a daydream ~ Action without vision is a nightmare"