Hi Victoria, I am just past my due date and patiently waiting on her arrival, however, let me tell you I had a flat stomach and weighed in at around 120lbs before I was pregnant. I am just now starting to get stretch marks in my final week! I literally cried! Its something we all worry about as women. Our bodies not being what they were. However, my usually tells you the honest truth DH says I look more beautiful now than ever. I fear C-section, scars, keeping weight on, and stretch marks, but would that stop me from maybe having another child in the future.. no. (Aside from the fact I only want one child to begin with). Children are a blessing either way. Your DH loves you for you, not how your body looks. and I am sure proper diet, exercise, and lots of fun playtime can help you get rid of the pooch. :) and i've heard breast feeding helps.
I wouldnt delay having another, just work on yourself afterwords and you should be fine. :) I agree with Tammy. Love your body and accept the things you cant change. You wont be young forever and weight is bound to sneak up on us all one day, its all in how you handle it before, during, and after that counts!