I'm glad you figured it out before you gained more. You're still well below your starting weight, so that is good. Is your doctor's scale one of the balance beam types? If so, it is probably a lot more accurate than a digital scale sold for home use.

I've heard that scales are less accurate when you get up close to the weight limit. I check my weight every couple of weeks on the balance beam scale at my local YMCA to make sure my digital bathroom scale (which I paid $17 for and which only weights up to 300 pounds) is still calibrating accurately.