"my partner and i were having protected sex but the condom broke (most likely they were too small so please note the importance of getting correctly sized condoms) and i took postinor sd (my recommended morning after pill with the active ingredient being levonorgestrel) within two hours. one week later i got my period but it was an extremely heavy flow!!!! the only other side effect i experienced was a tad bit of lightheadedness which admittedly was way better than having a baby i wasn&#039;t ready for."