i over heard my boyfriend watching porn

when my boyfriend and i first got together i told him i didn’t really like him watching porn. it triggers trauma from my childhood and i think it is disrespectful to our relationship. he said that it was fine and he wouldn’t do it. instead he would ask for pictures from me. we have been in a relationship for 9 months. over the last few months we have been going through ups and downs but we were still together. which throughout that time i didn’t take pictures or anything because of everything that was going on. we try to facetime every night no matter what since we can’t be together everyday. last night i over heard him watching porn in the background. it killed me to hear it, i said what the hell is going on and his response was “oops” and went on mute. he is aware i don’t like it and didn’t seem to care. i don’t know what to do or how to talk to him about it. what do i do.