Doc says I need to lose 50lbs, hubby says I need to lose the doc!!

So I went for my annual exam, and to get a blood test since AF hasn't come yet and I'm going on 8 days late. My doctor looked at my charts and the only thing he wanted to talk about was the fact that I had gained weight. I'm 6'2 so when I gain 25 lbs I carry it much differently from someone shorter. Not saying that I should use that as an excuse, but I am frustrated bc I feel good at my current weight. My hubby LOVES me at my current weight, but the doc said if I don't lose FIFTY pounds he's gonna put me on Metaformin. Pleeeeease someone give me some insight on whatvit is/does. He knows I'm TTC but this is only my first month actively trying. I just felt like he should have done further testing other than looking at the heavier weight and immediately saying I could be pre-diabetic. I'm so down about it.....I'm gonna attatched a current picture of myself. Do you guys think i need a second opinion???