I have been on the pill for a number of years now only stopping to fall pregnant with my son. My periods had always been regular with red blood and lasted around 4 days. I then went on the mini pill as I breastfed. Once this was over I went on the combined pill again. I was not experiencing normal flow and the blood was dark I spoke to the nurse who put me on loestrin 20. I have given this a few months to settle in my body however my periods are extremely light I have no fresh red blood it is always brown and not even enough to use a tampon (sorry tmi). I am not pregnant however I am worried as before I had fell pregnant my periods were normal. Why are my periods dark brown blood and very light. They last for a few days but it's barely anything. Didn't know if it was just hormone change in my body and nothing to worry about.