I am suppose to start my period today (July 9th) and I usually have a heavy 6 day period. and now i have a really light period! Does that count as a missed period?? and also i have the Gardasil (HPV) shot on June 14th and i was on my period when i received the shot. would have that vaccine have something to do with my period changing? I am really just wondering if that counts as a missed period? because im trying to find out if i am pregnant or not. Because i had sex on June 22 (the condom broke) and i have a normal 28 day cycle and the day i ovulated (as of what mymonthlycycles.com said) was on June 25th. so that was 3 days and sperm usually lasts 3 days long however there still can be a chance!