Sade moment.

I woke up in the middle of the night rushing to the bathroom and realized I had just started my period. I'm pretty sure I did not ovulate but I'm trying to understand how do you get positive ovulation test but don't ovulate??? In a sense I'm kind of happy I did start my period because I am completely done taking in any kind of birth control so now I'm going to go pick up my prescription for my clomid and then my dr is going to get me back in to see if I'm creating follicles. I really hope I am. It's been a rough couple of months starting in September of 2015. I'm just praying that my tubes are not blocked again and everything is still ok just haven't ovulated. Does anyone know how well clomid works?