My boyfriend and I are in love and had spur-of-the-moment unprotected sex just a few days after my last period. My period is due right around now, and I'm experiencing symptoms such as headache, nausea, abdominal pain, tender breasts, sensitivity to scents, constipation, and fatigue.

Could I be pregnant, or is this just my mind playing tricks on me?
Please give me some advice. It would be greatly appreciated.