Uy, yan talaga common side effect ng injectable, lalo na sa first few months pagkatapos mag-start! A few of us moms tried it and halos same experience namin, one of my friends spotting din for like six weeks, another one naman lighter lang after two months. Ang body mo lang nag-adjust pa sa hormones, so usually nag-normalize after a cycle or two, pero kung concerned ka talaga or patuloy pa after next month, mas better mag-check with your OB na lang para ma-rule out anything else at makasiguro ka!