Hi, I have been having lower back pain for about a week now, with no period (about 3-4 days late). I have done four home pregnancy tests which have all been negative (in the last week). I had an old Implanon removed and a new one inserted about a month and a half ago. The pain feels like a band across the top of my butt, directly above where the butt cheeks finish along my back. I ve had normal bowel movements, although I do have some mild pain when I poo. Urine is fine.