I never regretted having my son, but I regret that I had him too young, in my opinion. I was 22 when he was born and at that time didn't want kids, he was a surprise to me and my fiance. Even though I felt I was mature at that time, I realize that I was still too selfish of "me time" and still didn't know what I wanted in life. My thoughts were "how can you raise a person to know what they want in life if you don't even know yet?" But everyone is different, you might be more than ready, but my suggestion to you is to wait a little bit.
#1. Your going to be married next month, enjoy learning to be a wife first. There is a lot of things you won't be able to do as a couple because you're too busy with the baby and you will miss it. It is easier for guys to go out than it is for Moms for some reason. You may not know it, but there is a big difference between being boyfriend/girlfriend and being husband/wife. Take time to learn each other in that aspect before bringing in anyone else. For my husband and I, even though we were engaged for 6 months before we were married, it was a very stressful time for us to have become pregnant when we did and I think life would have been easier for us as a newly married couple had we not had a baby right away. There was a lot that we missed out on like couples nights out.
#2. Your fiance has already told you that he doesn't think it would be wise to have kids so soon. If you did, how would he be with that kid? Remember, men mature differently than women. You might be ready, but if he's not, then that might lead to marital problems between the two of you. He might start doing things to come home later than usual, stay out with the boys more, and leave you with sole responsibility of the house work and baby. You might grow to resent the freedom he takes. Additionally, respect his decision. He's trying to tell you his feelings. Having and raising a baby is a team effort. He is telling you that he's not ready to do that yet.
I have a friend who got married to a young man and ended up getting pregnant right away because they both thought they wanted to. At first things were okay, but then he started doing exactly that...longer nights at work, going out with the guys, taking his co-workers out for drinks after work, etc. Finding any reason to stay away from home and the stress/responsibility of family life. They separated no more than 4 months after the baby was born. It was too much responsibility for him to handle. He still wanted to have the freedom that he felt he lost when they got pregnant. And she became bitter because she was always left home alone with the baby when she too desperately needed some alone time. Her partnership dissolved into sole-proprietorship and she hated him for it. She was always so focused on the baby that she started taking less care of herself (no make-up, looser clothes, not doing her hair) that he didn't find her attractive anymore and that too ended up with him cheating. His sexy new wife was now a mom and taking care of someone else than herself, him, and them.
All I'm saying is, give your future-husband the time to grow up a little more and be ready. It might suck for you, but it might save your marriage if you just have a little patience for him. Men do not mature quicker than women. Enjoy the idea of being able to come home and jump each other's bones in the kitchen if you want instead of checking on the baby. Kids are worth it, but they need both Mom and Dad there and wanting them. They are a HUGE responsibility that you cannot take lightly.
Good luck to you and congrats on your upcoming nuptials.