are you TTC? you need to track when you are ovulating, then have sex around ur ovul days, or if you are not planning now, just use protection.
You're not fertile on/just before your period, so it's highly unlikely that you would become pregnant then. Have you had sex after this? If so, then you could be pregnant. Only way to tell is to take a test. If you're not trying to conceive, you should using condoms and/or birth control at all times. There, strictly speaking is no 'safe' time to be having sex if you're not wanting a baby, but chances are slimmer on your period.
the only way to know if your pregnant is to take a pregnancy test since your already several days late a cheap one should give you a accurate result just follow all the instructions exactly i can't tell what your chances are most women can't get pregnant on or around their period but since you don't know when you ovulate then there is a chance that if you ovulate soon after your period then you could have gotten pregnant so the only way to know is to test good luck and if your not trying for baby then there really is no safe time to have unprotected sex so always use a condom