Talk me down.

I'm really, really upset right now. I'm 7w5d pregnant. I have had horrible exhaustion, no morning sickness, just debilitating exhaustion.
Today, I told my husband that I was going to cancel or pause my gym membership because I am too tired to go. I don't work. My husband has been very insistent about me keeping active, partly for the health of the baby and partly so I continue to be skinny. When I told him I was too tired to go to the gym, he said, "if anything developmentally happens to our baby, it will be your fault." I was so upset that I called my parents and told them, which upset my husband even more. I don't know what happened. He's usually so sweet. 
I have been crying for the last 3 hours. My stomach hurts. I know this can't be good for the baby.