I'm trying to read through, it sounds like "a baby" is being thought of no more than an object to dress, play with and feed.
DH had our ducks in a row, we were self supporting, and even when I had to stop working from complications from pregnancy (heart issues, hypermerensis, appendectomy, kidney failure), we were able to live on his income alone for over a year.
Children completely, utterly turn your life around. It's been almost 4 years now since we conceived DD, and I don't think I've slept a whole night since - either getting up with DD, or waking up and checking on her. I don't think I will ever sleep a full night again, meaning a whole 8 hours. Even being drugged at the hospital for surgery, I didn't sleep. I can't anymore.
You can take your plans pre-baby and toss them out the window. All of them. When life isn't about your and hubby any more, but all about the kid, things change. Plans change. Priorities change. Those priorities almost never match up pre-kid and post-kid.
They grow up too. They sass. They hurt you, scream at you, call you names, make you feel like the worst person in the world. They do crap that makes you race to the hospital or call poison control, and then you pray inside that the poison control people or the hospital doesn't call CPS on you because the kid managed to climb a chair, table, and then on a stack of books to get your medication - and you don't even know if they ate any.
I've read once that toddlers are incontinent little task-masters. Even now, DD just came up and asked for a cup of milk. I was typing. She got in my face and said "I talking to you! I talking to you mom!" Then we had a talk that it's not nice to interrupt, and she can wait a minute, and she needs to say please. Then I get her cup.
There is no price to put on kids, birth, diapers and all that. It fades into the background, I think as a part of diminished mental capacity from years of lost sleep. You can't write up a cost for them, and know what birth to 18 will cost.
Get your life together and in order so you can provide a nurturing and caring environment for a child. You don't have that now, and it would horribly unfair to throw a baby into that. Get on some birth control and make sure you don't subject a kid to a quality of life they don't deserve. Parents should want the best they can give to their child, and it sounds like you have the plans and potentially the ability, you just need to act on it.
Of course, with every trial and stress DD puts us through financially and mentally, I wouldn't trade her for the world. That's why I still get up at night to check on her