Hey. I'm 19 yrs of age. My last period was December 19 2011. I had unprotected sex with my boyfriend December 26 2011.. I then had protected sex wit a friend December 30 2011.. I'm confused with this conception caculator ( I'm not sure what it means. ) I know you can't tell me exactly who's my baby father but I'm sure sonebody can help :) PLEASEEEE WRITE ME BAK ASAP WITH AN GOID ANSWER..