I feel like my first trimester is ruining my relationship

We did not have a planned pregnancy, but after a lot of thinking we decided to go fourth with this baby because we are at an age where it is no longer frowned upon to have a child. Parents weren't disappointed when we told them, and it all seemed like it was supposed to happen in the first place. I am ecstatic for this baby, and my boyfriend is nervous but he has little moments of excitement too. I can tell, the pregnancy has blown out our spark. I don't know if it's normal to not feel like getting intimate with your boyfriend while you are in the first trimester(11w3d), but I just plain do not feel sexy. I do think he tries to understand, but how far can understanding "my girl got pregnant and now she doesn't put out" go? I don't want to be that girlfriend. I want to be that girlfriend that he hears the horror stories of people getting married or having children and they stop getting intimate and he laughs because his girl isn't like that. Ugh save me from my ugliness. The acne, my hair falling out, the lack of motivation.... the horror. LOL