PCOS, Metformin, Clomid, TTC!!

I am overweight, diagnosed with PCOS and have been TTC for about a year now. I've been taking Metformin 50mg twice a day, and Clomid on my CD 5-9. I've been trying to test for ovulation using opk's but I've never gotten a "peak" response, just the "high fertility". And my last two cycles have been around 46-48 days long. I guess my questions are: Should I ask my doctor to increase my doses of metformin and clomid? And is it possible that I'm ovulating on such a long cycle and my opk's just haven't been picking up my ovulation??