Postpartum Period and Breastfeeding

So my daughter is EBF for a little over 5 months now. I’ve had 2 periods (one that I’m on right now) since she was born. I’m also on the nexplanon birth control. My periods have been super light for 14 days, and this period so far is going on 16 days. Like I said, super light period though. It’s brownish with some red color to it sometimes if I catch it just right. And I went a little over three weeks between my first period and this one. Is this normal?? Should they be last in this long? Or does it just need time to regulate out since I’m not even 6 months PP?

** my SO and I have also had sex three times this period since it has been light. **