After birth period begins when?

So i gave birth on sept 19, bled and spotted for 5 weeks then stopped. On my 7th week i had cramps and light brown spotting, i thought i was going to start my period but false alarm. it was just light spotting for 3/4 days. after that i haven’t received my period. Im not breastfeeding, i pumped for the first couple weeks but it wasnt working out so i stopped. when should my period come? My baby will be 3 months next week