I had unprotected sex on April, 19th. And a week later I had what I thought was my "period" but it was only two days and it was very light but I had cramps to the point where i couldn't walk and I would get really bad migraines to the point where I couldn't see at all. The area about 2 inches below my belly button has gotten hard and I've had really bad headaches and I've felt sick to my stomach. The smell of certain things make me nauseas and I've been hungrier than usual. I've also gained about 10-15 pounds since then. Is it possible that I'm pregnant?