Discharge and spotting

I started having brown discharge 4 days ago then it turned into brown spotting two days later. I figured my period was about to start (but normally it’s a full on blood bath when it starts.) My periods have been very irregular since stopping birth control years ago and breastfeeding for the past 3yrs but this app had it starting 5 days ago (it has been wrong before). I’m not sure what’s going on. I’ve also had pelvic pain on and off. Any advice?