I m on trinessa 28. I missed a dark blue pill(third to last) on January 3rd, then I started my period(normal) on January 9th. On January 12th I had unprotected sex. That following monday when my period finished I felt very nausea from the smell of my shampoo. Since then I have been having pregnancy symptoms such as darked nipples, noticeable blue veins , cramps, gas, constipation , and occasional nausea. My next period is due in a week. Could I be pregnant from missing that one pill?