Ovulation confusion

Hoping someone can give me some insight. My husband and I have been trying to conceive for 2 years now with no luck. We went thru our first iui last month which didn't work. We decided to try on our own this morning to save up money for another iui because our insurance does not cover it. I have been doing ovulation tests every day this month and I am confused because I thought I already ovulated this month but just for the heck of it I kept testing and I have another very positive ovulation test. Has anyone else experienced this?