Metformin!!

I do not have PCOS or endometriosis. My dr said that I am completely healthy and IF I have PCOS it is barely even there if any! And the ONLY reason he says that is because of my weight! So he started me on metformin! Is that normal! My blood work was all perfect! My hormone check was completely perfect. I'm confused. He seemed to be pretty confident that we would conceive in two cycles or less! 😱😍🤰🏻🤷🏻‍♀️ I'm so confused. I weigh 350 and I am 5'8! I've lost 60lbs and gained back 15! 🤦🏻‍♀️. Back to loosing this week.