It's going to be okay. Take a few deep breaths (seriously, they help!).
First off, you really do need to spend some time focusing on what you want your life to be. Don't listen to fear, but focus on that deep down voice that tells you the truth. Do you want to be a mama? Not just right now, but ever? Did you dream about having kids when you were little? Or were you more focused on a career or school? Age has little to do with being a good mama... wisdom is found at all ages, and often young mamas can have special connections with their children.
Second, money does not make good parents. Lots of people spend tons of money and very little time or attention on their children. Besides, IMO one of the best things we can do for our children is to opt out of the consumer culture. There are lots of ways to be a good, healthy, frugal mama. That said, are you able/willing to find/take the kind of jobs you might have to in order to provide the true necessities?
Third, have faith in yourself. If you find that you really do want to be a mama, then you have to believe that you can and will be the best mama that you can be. MDC is a great place to find the support that can help you be that mama. I'm on my fourth (wow, that feels weird just to type that) and MDC helps me refocus my parenting every single day... I'm a terrible lurker, but I'm literally ALWAYS here.
Fourth, take some more deep breaths. And then some more. From someone who has BTDT, it gets better. The place you're in right now is HARD, and there are very few positive feedbacks to help you feel better (thanks morning sickness!!). But, it really does get better. It may get worse for awhile (and I'm not just talking about the pregnancy), but it will eventually get better. It will be extremely hard work, and you have to make sure that you are taking that work on b/c you truly want to, not for any other reason. But, if this turns out to be what you want to do, it is doable.
PM me if you need to talk. My life is very different from how I imagined it. Now I can't imagine it any other way. No matter what you decide, it will be okay.