I am on the mini pill and breastfeeding my 1 year old child. I haven't had a period since giving birth. About a month ago, I had unprotected sex and he ejaculated inside me. After that I had a tingly feeling in my uterus like a pressure or something. 3 weeks after the sex, I started bleeding (assuming it was my period) but it lasted for 3 days and was heavy then immediately stopped.  Now, the tingly uterus is back!! I don't understand what this could be. I thought i might be pregnant but why would I bleed for 3 days? I took a test before the bleeding and it was negative.