I have been having really irregular periods since beginning college which is unusual since I have been pretty regular since I started my period. The past two months, I have had my period right on time but in september I had my period on time and then had it again a week later. Then I had my period on time in october. But now it is november and I had what I believe is my period 10 days early. After looking around the web I heard things about implantation bleeding so Im freaking out. I had sex 3 days before my period began and it was protected. The period was lighter then my normal period but still changed my tampon twice a day and it lasted for 5 days. my blood was red and a little brown which Im used to. So i just want to know really if pregnancy is something I should be concerned about.