I understand your disappointment and frustration! I O really late.. I was testing all month starting on like cd 8 and nothing nothing nothing.. I ended up running out of opks around cd 28 or so... and I thought of buying more but figured I was just done with them, it was more frustrating than anything!

I finally did o on cd32. I never got a positive becusae of running out.. Opks' are not *necessary*, but if you like them then keep testing. Your plan of bd'ing when you see fertile cm is probably your best bet, I would definitely keep up with that.