There is always a possibility, no matter when in your cycle, if you have unprotected sex you can get pregnant. It's a misconception that there is a 'safe' time when you cannot get pregnant. Since you said your period was late, you may have ovulated later than you thought. It is probably unlikely since you have gotten your period, but If you believe you may be pregnant, the only way to know is to test or to go to the doctor. Good luck!
oh and the sex happened around 6 or 7 weeks ago