Partner watching porn

Let me start this off by stating I’m not against my partner watching porn . It has never bother me

I just gave birth 5 weeks ago to our 3rd child so we haven’t been able to do things and today when my partner got home he had his phone on the table connecting his new earphones and I happened to see a porn video playing I didn’t say anything but he hurried and pick his phone up . I got a little salty about it and I can’t figure out why if it never bugged me before