ladies help!

Abby • 31 years old. Married to Eric and mom to 2 year old son Jace! Second baby boy due next month💙Mom of boys 💙💙
Okay so at my 30 week prenatal I have gained a total of 37 pounds! (It was in the afternoon, with clothes on, and drank 2 bottles of water and ate lunch and breakfast). I'm no longer being able to walk much for exercise due to bad pelvic pain. I drink tons of water and don't eat much at all. I need help trying to figure out what to eat to either lose some weight, maintain, or just stop gaining. I do understand some people retain more water than others but the scale is very frightening. I am very constipated as well. I have to take iron pills daily for anemia and I take two stool softners daily as well. So I know not going to the bathroom is not helping my weight. Does anybody have any suggestions on certain foods to cut out. And please for the life of me don't type your pregnant your not supposed to diet. My son is fine he's actually measuring two weeks ahead with all my weight gain. I basically want to manage and stop gaining so much weight. I was very skinny before I got pregnant but still I've got about 9 weeks left and I'm getting nervous if the scale doesn't stop going up. Thank you! ❤️