blue,
Just start with your math where you feel most comfortable. I started with arithmetic when I was 22 years old, and I just chugged along. Don't ever think you aren't a "math person" either... That's all b.s. American schools screw us over mathematically, and we think we suck at math when we really don't. Since I started with arithmetic when I was 22 (I continued by teaching myself algebra, trig and pre-calculus), I've taken 3 semesters of calculus, differential equations, 3 semesters of calc based physics, and linear algebra... All with straight A's. And I was very bad at math before I became interested around the age of 22.
I'm 28 now and I just got accepted as a transfer from my community college to Northwestern University as an electrical engineer and they gave me a
huge financial aid package (almost a full ride). So I would also advise you
not to rule out the more expensive private universities. Do well at your community college, develope good relationships with your teachers, write good essays for your transfer applications, and you will stand a good chance of getting into an elite private school. I'm not advising this path simply because such schools are "elite" (you can get just as good an education at less selective schools), but they have a crapload of money and give really good aid. So if you are low income and get into an elite school, it's very likely that they will give you very good financial aid. (Even better than most freshman, since you would be considered as an independent student.) I would have ended up paying more if I went to my state school!
But what you need to do
right now is to start working on math problems
every day. Get yourself warmed up by doing maybe only 15 minutes of math a day. But stick to it until it becomes a habit. If you eventually start doing an hour or so of math a day, you will be amazed at how much you will learn. But just don't get overwhelmed. Just do something every day. If after a few months of preperation you start at a community college, and take the appropriate class, you'll probably blow all the younger students out of the water.
Engineers need to be very efficient self-learners. That's the skill you need to start developing now more than any other.
Hope I've helped! And good luck!
Edit:
I forgot to mention that I dropped out of high school when I was 16. So trust me, just about anything is possible. Apply as a transfer from your cc to MIT, if you feel inclined (although I'll warn you, they only accept 4 or 5 transfers per year

).