I think you hit in on the head when you said "Pre" preg. body. Even those perfect body mommas don't ever look like they used to. Sad to think they could look better, i know :_(
~>Instead of worry about getting back, focus on trying to be as healthy and in shape you can be. Here are my tips to get healthier:
1. Breastfeed, this not only is better for baby, but it helps you lose weight by burning hundreds of calories a day!
2. Since your baby is about ready or is already eating some food, set a good example and cook natural foods that you can eat and you can puree for baby. ( trust me its cheaper then pre-made and taistes better for baby too) foods that are great are oat meal, fruits,eggs (whites if you can handle that) Veggies, meat that is not fried
3.do baby workouts: stroller walks, play groud play (trust me you get a good sweat if you play right) you can use your baby on your belly or legs to add weight while you do leg lifts and but lifts.
4. plenty of water! For ever caffinated beverage drink 2 glasses of water.
Hope this helps and try not to worry. It took almost a year to get it on it may take at least that to get it off. Once you do, accept and love your new mommy figure, you earned it! ((Hugs))