Didn't read other answers but:
Make sure that your one session a week with weights is HIT. You don't need more than one a week, but make sure that one counts. Body by Science is a good HIT routine.
Have you had any glucose tolerance tests done? A1C?
Low carb with exercise is definitely beneficial for either fixing or at least better management of metabolic syndrome, so you are on the right track.
Sometimes there needs to be some healing and metabolic cleanup before you move on to your next phase of fat loss. In addition there are water fluctuations that could hide fat loss. Ie. you could lose 5 lbs of fat and gain five pounds of water without a noticing, and this would not even be strange.
As for metformin check out this post by Robb Wolf http://robbwolf.com/2012/03/09/paleo...ion-metformin/