Bleeding 5weeks pp?

Today I started lightly bleeding brownish/reddish blood. I’m almost 5 weeks pp. my doctor gave me the okay for sex since I was healed and I stopped bleeding about two weeks ago. So last night I had sex. She said if’s possible to have “ break through “

Bleeding up until 6 weeks. Just wondering if I should count this bleeding as my first period or what she was talking about. Or if it’s from the sex ?