I have been using opk strips to test for ovulation. I know that when I get a positive surge it means I'll ovulate 12-72 hours later. I had a positive last night at 8pm and another positive this morning at 10 but now at 12 it's a negative again does a negative mean the hormone is going down because I ovulated or will ovulate today? I know I should check my temperature but I'm just getting into ovulation testing so haven't tried that yet. Does anyone know? Thanks