I also struggle with understanding weight gain. I mean you are definitely expected to gain 25 lb on average. If you were underweight before, then you should gain like 25-30, if you were overweight before, then 15-20, and if normal, then 20-25. My doc gave us a book that shows the expected weight gain based on # of weeks but it shows a linear graph. That, to me, means that every 2 weeks I should be gaining 1.5 lbs at most. But based on what other women have told me, weight gain is not going to be linear, it might plateau sometimes, and then peak other times depending on baby's development. So basically my answer to your question is...........no idea
But when you go into your docs or midwife, they should be able to tell you if your weight gain is on track.
Like you, I felt fat for a while even though my weight gain was on track. I found that exercise did help me feel more in shape. I try to exercise at least 30 min a day: walking, swimming, yoga. It's tiring for sure, but I was a little concerned about GD given family history so I was extra motivated to exercise, and I think my weight gain slowed down a bit as a result and I certainly felt more fit and not fat anymore. Getting the appropriate maternity clothing helps with that too, trust me. Don't expect to fit into your regular clothing anymore, that's gonna make you feel fat for sure