In your experience what is most accurate to tell me if I've ovulated? I'm been charting both for first time this month. I have not gotten a positive OPK at all, but my BBT dropped slightly then rapidly increased a couple of days ago, which I'm assuming indicates O? The OPK test line has never come out as dark as the control line, but yesterday it was even fainter when I tested (which ties in with me having already ovulated I guess). Any tips? Or is there a chance I haven't ovulated at all? From my reading I'm led to believe BBT is most accurate but not as useful because you find out after O it happened. Help!