Irregular period after baby?

This is my first baby so I’m hoping you guys can help. My baby is formula fed.

I have always had super regular, like clockwork, periods.

I had my baby in March. I didn’t get my period until late June, about 13 weeks pp. it was like my typical period and lasted five days as always. I was supposed to start my period this month around the 22nd. Last night, I felt really bad pain on my right side and realized I was having ovulation pain. I’ve had them before being pregnant too so I know what it feels like. I took an OPK and it was very dark. This would mean that I wouldn’t have a period this month since I usually have my period two weeks after I ovulate.

I’m not super concerned but is it normal to be irregular for a bit after baby? Will I eventually get back to a regular cycle?