Hi my name is Caitlin. I started metformin on Dec 22 2014, had regular periods Jan and Feb on the 10. I have not gotten my period this month. My breast are heavy, very tired and getting stretching pains in my groin and uterus off and on, on both sides. I have back pain and headaches and some times when I stand it feels like I m in a bubble. In morning with coffee I get acid reflux.I have never been pregnant and have Pcos. I have had cervical cancer cells removed and have had pid in the past. Could The Medicine messed with my cycle or should I go buy a pregnancy test. Thank you Caitlin