Spotting after my period...

I had bleeding for a good 4 weeks after I had my son. Then it stopped. I finally got my period around 11 weeks pp and it lasted 7 days. Now it’s 6 days later, and I’m supposed to start ovulating, but last night, began spotting. To the point where I had to put in a tampon today. What is this?!

The day before I started spotting, I had sex with my husband. Unprotected, but we use the pullout method.

Thoughts on why I started bleeding again when I should be ovulating? I ebf.