The Condom Broke And He Came Inside Me. I Took

The condom broke and he came inside me. I took plan b about 9 hours later. I was supposed to get my period 1-3 days later but I didn't. I have had headaches all day everyday with cramping. But now a week and a half later my stomach is feeling weird. I get pain up close to my ribs and in the middle of my stomach. Could I be pregnant?