Period - Where are you?

So I had my baby 12 weeks ago and he was 8 weeks early. I pumped for about a week and a half before it became to much with everything going on. My concern is I still have not had my period. I bled for maybe 3-4 weeks after delivery and since I had two separate days of spotting on it when wiping in the last 8 weeks since my bleeding has stopped. Hubby I fooled around one night but no penetration just hands and such. I was so paranoid though that I’ve taken 3 pregnancy test to make sure. I saw my OB at 8/9 weeks postpartum and she wasn’t concerned that it hadn’t returned. I’m not back on BC yet but I have been overly stressed. It’s really bothering me it hasn’t returned not that it’s enjoyable but it feels like my body doesn’t know what to do and that bothers me.