Hello, is it possible to be pregnant if the last time i had sex was on august, i took the day after pill, and had my regular period every month since but now i'm two weeks late which is not usual at all for me?

If the last time you had sex was six months ago and you have had normal periods since then, then you’re not pregnant. You can verify that by taking a home pregnancy test if you are worried, but it is really not necessary. If you are not having normal periods, see your gynecologist. Good luck.

You do understand that the shedding of your uterine lining (your period) means that you're not pregnant during that cycle. You've had 5 periods since then. A late period can be due to so many factors. See your OBGYN for further guidance.