Yup, I can have huge swings from day to day or even in the same day. And, it's really of no importance whether your scale matches the Drs. or not but it is important for it to be consistent. If you step on and off it, it should give you pretty close to the same weight.
I always try to wear the same thing, weight at the same time, make sure the scale is in exactly the same place, and step onto it in the same way.
Weigh once a week and you'll save yourself some heartache! If you accurately track your calories and are on average well below your daily calorie burn, you can rest assured that you will (usually, as plateaus DO happen) see a loss.
47 M 5'8"
May 4, 2010...... 440? lbs. (Start FitDay Size 60 Jeans)
June 19, 2010.... 393 lbs. (First Weigh-in)
June 19, 2011.... 229 lbs. (164 lbs. gone in one year :-)
Current Weight... 185 lbs. (Size 36 Jeans)
Next Goal 169 lbs. (07/04/12)
Ultimate Goal 165 lbs. (12/31/12)
The best exercises for weight loss are Fork Putdowns and Table Pushaways.