What Causes Radiating Pain From Lower Back To Abdomen And To Breast?

I have mirena and lately, right before my period starts. i have extreme lower back/ kidney pains slowly radiating up to the top of my back. then it slowly works its way around to my abdomen to right underneath my breasts. ive already been to the ER for this once before and they told me possibly endometriosis. i just want to know whats wrong with me.