feeling down

Everytime I go to a prenatal appointment my weight goes up:( it's not like I eat really unhealthy. I'm afraid I'll hit 200 pounds or more by the end of my pregnancy. I weigh 175 now and I'm only 11 weeks. I feel like crying all the time. I feel like I'm doing something wrong to be gaining 3 pounds a month. Does anyone else struggle with this kind of thing? I feel so alone