[Jack]

Now, there are no definitelys when it comes down to pregnancy. Just having sex without protection does not mean you'll be pregnant, you have to be at the right stage of your menstrual cycle to get pregnant and there are only a few days per month you can conceive. However, it's still a possiblity. A good indication how likely you are to be pregnant might be to think about when you last had your period and then figure out when you'll be most fertile. Most women are most fertile from days 12-16, so if you just had your period or are just about to have it the chances are less likely (although still not impossible).

The only way to know for certain is to take a test.