Postpartum periods - how long until they’re normal?

I gave birth to my baby boy on September 1st. I breastfed for almost 2 months but as soon as I stopped I had my first period. Was a bit shorter than my usual periods but I didn’t think much of it with it being my first after birth. Since then my periods have been all over the place. After my first period I went 31 days before the next one began. This time I’ve only gone 19 days!! What is going on? Should I be concerned?

We would like to start trying for baby no2 but I’m concerned that my irregular periods might indicate infertility.

Before pregnancy I had a very regular periods. Cycle length of 26 days and I could almost put a time on when it would start so this is all very new territory for me.

Also, I’m not on any birth control as I wanted things to go back to normal naturally.