Wtbfail, let me tell you my story.
I basically stopped going to school in 7th grade too.
When I turned 16 (min. age) I bought some GED study books, studied, and took the GED.
I then took a semester at a community college because I needed the credits to join the Marine Corps.
When I left the Marine Corps (4 years later) I returned to a community college
and worked toward a transfer degree (pre-engineering) to go to a university.
I worked hard and ensured I got excellent grades.
That right there opened up every door I needed.
Now I am about to finish my BS in electrical engineering at the very top of my class.
I am going to be able to apply, and most likely be accepted, to any grad school I choose due to my near perfect college performance. I already work as an engineer and make more money (hourly) than almost everybody I know.
I've had a lot of people look down on me and talk trash, thinking their HS diploma means something.
I'm more successful (both academically and financially) than all of them and have only just begun.
So just keep that in mind. It all boils down to how hard you're willing to work.