How much porn is to much???

I am 10 weeks pregnant and most days I'm nauseous and tired. I'm not in the mood. Let me preface: before pregnancy we had no issues with sex. I took care of him and vice versa.

At this point he is literally masturbating and watching porn every free second he has because I don't feel like it. Am I being selfish because I feel like he should care just a little bit more about what I'm going through?? I mean last night for hours he was looking at porn. I'm not exactly sure how to feel. I'm a little disturbed but should I be if his needs aren't being met????