Nursing mom wanting to get in shape

HI, I'm new to this, but I'm a mom of a 2 month old, so I can't really diet cause I need 2000-2500 Cal's a day for milk. I'm trying to eat healthier though, but it's hard when I have bloodsugar issues and want to loose weight. I also have Diverticulitis, so too much fiber and I can end up in the hospital. Catch 20/20 I guess. I'm starting off slow, but having hard time getting all calories in with watching sugars Any good recipes that are quick, low carb, high protien and fiber? What works best for fitness? I've started walking at 3.0 mph up a 3% incline for 15 minutes everyday this week, next week I want to aim for 30 minutes.