Unprotected sex before period

My boyfriend and I usually use the withdrawal method on my least fertile days, and a condom on my most/moderately fertile days. However, I read online that having sex (and being ejaculated into) close to, or on, your period only presents a very mild risk of getting pregnant So the last week, my boyfriend and I have done this and today I got my period. My period is much lighter than normal though.. and now i'm paranoid could I be pregnant Thanks in advance for your thoughts