I had unprotected sex on 17oct and took unwanted 72 on 18 oct i.e. after 26 hours. After that I had my normal periods on 1st nov which was my expected date of periods which lasted for 4 days and flow was heavy. Now again I had my periods on 26 nov which was expected date but it lasted for 2 days only and flow was normal but normally I have periods for 4 days. Is there still any chance of pregnancy? Is periods of 2 days normal? Is it due to the side effects of the pill?