I had sex with a guy a week ago. He didn't wear a condom but he pulled out. I'm not ready to be?

there is always a 50/50 chance after unprotected sex. The only way to really know is to take a pregnancy test or visit a doctor.

And I tell this to most people. Abstinence is the only 100% way to not get pregnant. using the pill and a condom is the best way to prevent an unwanted pregnancy.