I'm 5'4" and now thanks to low carbing - I guess- about 120 or less. I started at 142!

Weight charts don't take into consideration body frame, which is the actual size of your skeleton. This matters because larger "frames" have more of all body masses (muscle, tendon/bone - even blood!) and this all plays a part in the total weight of a person.

Sounds like you are kinda into the numbers of things...if this is consuming your thoughts - you might back off a bit...if it is stressing you at all.

I never weigh now - even when I go to the doctor I tell them that I choose not to know my weight. When they ask me why, I tell them "I choose not to know". Never had any problems.

I know I am smaller/thinner because I sold all my 10/12 clothing on ebay and now I wear 1-4's depending on the maker/style - and that's the best (healthiest way) to know - if you asked me...

but that's just my opinion.
N