Period 4 days late. last unprotected sex was in april, had 2 periods since. now instead of period i'm having signs of ovulation. what could cause it?

Pregnancy: Your history suggests that since your last unprotected sex in April, you may have conceived during that time. The intervening “2 periods” may have been misleading, while the newly created embryo was struggling to implant. Perhaps this implantation has finally succeeded. This would cause your current signs of ovulation, in absence of current period! Suggest performing a simple pregnancy test!!!!