How do you know you ovulated the day before? Are you charting? It is possible to get a positive OPK for a few days. Mine always last 3 days. Your hormone surge can be detected by the OPK on the way up and again on the way down, so it's possible that your OPK is still positive because your hormone levels are still high. You can't really pinpoint the day of ovulation though unless you're charting.
PCOS--TTC since 11/2010:
5 cycles of Clomid: all BFN, 1 cycle of Follistim:CP
1 year break thanks to deployment.
1 cycle Follistim: BFN, Lap to remove peritubal cyst May 2013
2 cycles Follistim + trigger: BFN, Gonal F +IUI April 2014: BFP!!!!!!
From what I've read, your LH surge can last a few days, and you ovulate about 12-24 hours after the peak of that surge, so you can, I think, have a positive OPK (on it's way to negative) after you've technically ovulated. Your LH is still high enough to show positive, but it's on it's way down.
Re: positive OPK after ovulation?
Thx for reply. My chart is at bottom of siggy...