Goal: Lose mommy weight

Hi. I just discovered MFP yesterday -- so glad I found a tool that can help me get healthier and stay fit. I have a 2 year-old son, and I still have not really lost all my mommy fat and wish to reach the ideal weight for my height. I am 5'3, currently 130 lbs. While it may seem like an easy task to lose 15 lbs in an indefinite amount of time (as I am not in a rush), I have struggled to lose more than 5 lbs and keep it. I still look pregnant, as my tummy still bulges. But more important than losing weight, I'd like to be healthier. I get tired so easily and I can't even climb up more than 5 flights of stairs. I know this may be a result of lack of exercise and a not-so-good diet. So hoping for a healthier me. I'm looking forward to being a part of this community.