I am so sorry for the heartbreak you had. I am glad they have a solution for the next time..small consolation I know, but I am so glad you won't have to suffer that again.
If you had a positive test today (test line as dark or darker then control line), then there is no need to test again. OPK's can't tell you when you will ovulated exactly, just that the LH hormone has or is surging. When that happens most will ovulate anywhere from 12 to 72 hours after the first positive test. The average is 36 hours. So no need to repeat..some women will have it stay positive for a few days, others just a few hours. Just get busy!!! Good luck, I hope this is the month for you. Lots of SSBD!!!