My tsh is around 3. fatigue, low energy. have pcos and insulin resistance. can i be suffering from hypothyroidism? is there a link with metformin?

Thyroid: Most US laboratories will report a TSH of 3 as "normal," but most endocrinologists in 2014 consider normal or be under "roughly" 2.5 (dissenting opinions welcome.) It's so close you might get different opinions from different doctors whether this makes you hypothyroid or not, but it's a close call either way. There is no association between metformin and thyroid function.