Hi, I have been having pain in the right side lower abdomen for the last few days. Itz more like pre menstrual cramps but I have it only in the right side. I had sever lower back pain a week back and it was more in the right side and now the frontal part is paining. I am 20 DPO today and I normally ovulate around CD 20 but my OPK's have been coming back negative the last 3 days. Also, I had only 2 days of period last time and 1 day of mild spotting. I did suspect it to be implantation but all my HPT's have also been coming back negative. Any suggestions why I have pain in the right side alone?