What's going on?

Yesterday my boyfriend pulled me off the couch and started taking off my clothes, kissing my neck, etc trying to get me in the mood. I felt dirty because I just went to the bathroom and was asking if I could go clean off and he said no and grabbed me (which I usually like) and pulled me into the bedroom. When I kissed him I didn't feel like "oh my god I want him" I just felt really uncomfortable and weird. I finally was able to clean up and I still wasn't in the mood. We did have sex but the whole time I just felt really strange. We've been together for 2 years and I just got back from a weekend trip I took without him. I should want to jump his bones, right? I blamed it on me being self concious, which I am, I didn't feel sexy or turned on at all. He even tried to go down on me and I wasn't into it I made him stop. What's wrong with me?