... I've been on the shot since Oct 2016. Just had my 3rd shot last week. My period before was very very heavy. Now on the shot they are light, lightier than I have seen in like never... I'm not use to having light cycles. I'm use to wearing the thickest, longest pads. Changing them every 15 min no lie... I thought with the shot it was supposed to help stopped things like passing blood clots, endometriosis pain (which I have). My periods are light but still very painful and lots of cramping