I Had Unprotected Sex With My Bf On 19 Sep

I had unprotected sex with my bf on 19 sep right after my perids. I took postpone 72 after almost 70 hour of sexual intercourse. I have irregular periods, the cycle is 22-25 days on average. So i usually bleed 5-7 days before due date. today It is 12 oct, my last periods were on 13 sep. I experience light bleeding yesterday nd today (11 and 12 oct). So im i safe?