I took Plan B One Step on Jan 2nd (sometime after 5pm), following unprotected sex on New Years Eve, after midnight (Jan 1st). My menstural cycle started on Jan 15th (just 3 days early). However, I am still bleeding & cramping today (Jan 28th). Do I need to be concerned?? Secondly, the medication I purchased contained 1 tablet only, as I search for answers, it seems there may be a 2nd dose that I may have missed... Is this information accurate?