Feeling like a cow

Or a hippo maybe, I think they're more round. I've gained 7 pounds in the past month. It's also just 7 pounds in the past 3 months, but I'm only supposed to have gained 3 pounds over the past 3 months, for a total of 15 pounds through this whole pregnancy. I feel like a fat worthless slob. I look nothing like a pregnant woman, I look like a fat obese monster who can't control herself. But here's the thing. I DO control myself. I walk a mile everyday, and when I can't walk outside I borrowed mom's Gazelle and work on that for AT LEAST a half an hour each day. I eat NO junk food, I have one can of soda a week, just to curb my caffeine headaches. I just feel absolutely disgusting. From going from 180, to 250 in less than 6 months, and being told that nothing is wrong with me is hard enough 2 years later to deal with after being unable to lose any weight. But now continually gaining weight and being completely unable to do anything about it, and unable to see any kind of baby-bump, I'm somehow supposed to be comforted by the fact that this is supposedly all for the baby. If it's for the baby, how come I look like a hippo, and not pregnant?