at the end of march i got my period normally and it lasted for about 4 days and the day after i stopped bleeding i had unprotected sex and then i decided to take the plan b the very next day. i took the first pill at 8pm and then then second pill the next day when i woke up. 72 hours since i had unprotected sex had passed already when i took the last pill. and its been a few days since then and now i have my period which is not normal its only been a week an a half since i had my last period. could i be pregnant?