Pregnancy and Romance (or lack thereof)

I'm a FTM, and I'm so excited as I prepare for my baby! I'm also a newlywed. My husband is extremely excited, too. He was the one who really wanted to have a baby so soon. My issue is...since this pregnancy, I have not been in the mood for sex AT ALL..no type of sex!  It is the furthest thing from my mind, but I do feel bad for my husband. We've even argued about it. I don't think either of us anticipated this. I try to push through my feelings every now and then and just have sex to try to please him, but the last time I did that, I had a physical reaction of nausea, cramping, and soreness. I've explained to him that the idea of sex repulsed me, but he does not seem to understand although he claims he does understand. I feel more distant than ever from my husband. We hardly even kiss each other at this point. In addition to not having sex, I just feel like that spark is gone, and it has made me feel really sad and inadequate as a wife. I believe there are other ways to be intimate besides having sex, but I don't think he feels that way. Right now, it feels like we're simply roommates or just friends. Anyone else have this experience or something similar? BTW, I thought my lack of sex drive would subside after the first trimester, but I'm currently 20w1d.