Hi I am on the nexplanon birth control for 1 year and half never had and bleeding but this last couple of months I have been having spotting maybe two days at the most then nothing for weeks. I have had brown spotting followed by a large clot nothing for 1 week and now very light bleeding never enough for a pad but this time I have a strange tight pain in my left side and my lower back is very stiff and very tired run down. Should I be worried or an I stressing over nothing.