can i be pregnant? the first day of my last period was on 8/18/10. i had unprotected sex on these dates: 8/29/10, 8/30/10, 9/3/10, 9/04/10, 9/05/10, 9/06/10. i do not know if i have the 28 day cycle or not. i just want to know if you can help me out, give me answers, or whatever. thanks.