No. You keep track of THE FIRST DAY OF YOUR LAST PERIOD, abbreviated as LMP (last menstrual period).
Unprotected sex is risky, even the pull out method, which it appears you are using. If you don't want to get pregnant, you need to use protection EVERY time. There is pre-cum that can contain sperm. Men cannot contain pre-cum and they don't know when they have it. Also, you may have noticed they can hardly contain cum in any way.
When is your period due? Take a pregnancy test then.