I had an accident with a condom two months ago and took plan b less than 12 hours later. I had withdrawal bleeding 5 days later and my period came on time from the day that I took the pill and was relatively normal. However, this second month, my period came on time but is much lighter (less than a heavy flow but more than just spotting) and is very clotty. I have also experienced sore nipples and more cramping before my period arrived both cycles. I've taken many hpts which have all come out negative, and a qualitative blood test which was also negative. I am just slightly worried about being pregnant, but what could be causing the light period and when should I expect my cycles return to normal again??