Hi,
You can read this previously answered question:
How likely am I to get pregnant if I had unprotected sex but he didn't ejaculate?
To sum up, yes there is always a chance of getting pregnant if you have unprotected sex.
If you are concerned about pregnancy, you should consider taking the morning after pill ("Plan B" pill) that you can take up to 5 days after having sex, although it is most effective within the first 72 hours.
The sooner you use it, the less likely you are to become pregnant. If started within 72 hours, the morning after pill can reduce the risk of pregnancy by 75 - 90%.
