CD 38?!

So long story short I stopped my last BCPs in October '13. I had been on he pill for 13 years. The last year on the pill I never had a period. In November I started getting periods again and the cycles have gradually become longer. Last month was 35 days and currently I'm on CD 38. I had a positive opk on cycle day 17. I've taken 3 hpt in the last week and all BFN. I don't believe I have conceived but am wondering at what point do I see the doctor about this? Anyone with similar experience?