Why do I feel happier/better when I'm ovulating, and how can I reproduce those affects when I'm not?

Basically, when you ovulate your body releases Endorphins, little transmitters that reduce pain. These endorphins also make you happy. A great way to release them is to get your heart-pumping, whether it be after exercise, watching a scary movie, or laughing! A few other ways is to eat chocolate, or to be in the sun (when underaking this strategy make sure you are protected - slip, slop, slap). I hope you feel happy again soon.