"in a nutshell,  march 2017, i had a normal period; had intercourse with my husband around the end of march and took a plan b the next morning. within about 5 days i had another heavy period that lasted around 5 days. i figured this was due to the plan b. a week later i took another plan b around 10 hours after intercourse which caused me to have another 5 day long heavy period. this means in april i had what i thought was two heavy 5-6 day long periods. however, it is now the middle of may and i found out i am pregnant. according to my doctor i am around 7.5 weeks along which means i got pregnant during the first plan b attempt. i don&#039;t understand how i had three full length heavy periods but i am still pregnant??"