Is a two week early period or light spotting a sign of pregnancy?

[wannabemama]

I had unprotected sex with my husband February 26th-29th. Then my period started March 1st, ended March 5th. My next period was scheduled for March 29th or 30th.(I am very regular) But it started today, (two weeks early) March 21st. It is light bleeding, a deeper red, nor very bright. I'm feeling a little crampy and nauseous. I'm wondering is this is just my period coming 10 days early, or if I'm pregnant.

 

[luratraloora]

Did it progress and get heavier?