I am on BCP but this last pack I was on only had 16 active pills since I delayed my period before that pack, and then after the 16 active pills I went onto my 7 placebos, had my period and began my new pack. I have always heard that you lose your effectiveness of the pill if you do not have a full 21 active pills so I used back up of condoms and vaginal spermicidal gel and was wondering how effective that was? The condom did not break and I know I used the spermicide correctly from the instructions so what are the chances?