What Causes Delayed Periods With Headaches, Sore Breasts And Heart Burn?

I have been trying to keep up with my ovulation days; however, I have irregular periods and my cycle has been every 22 days according to the ovulation calculator. My expected period was yesterday but I did not start. I have bad headaches, sore breast and heartburn. Even though the ovulation calculator says I should begin testing today, I don't feel that I am pregnant because my ovulation date was three days before I had unprotected sex. It would be nice to be pregnant but I don't want to get my hopes up.