You're at the age I wish I had been when I got the flying bug. This is what I'd do if I were your age and in your shoes, and wanted it as bad as I'd like to now:

Finish high school, read everything you can about emergency care, bone up on your math and science skills. Go to college, or whatever training program you desire to become a paramedic and work your butt off to become the best one you can be. In the meantime, devote what free time you have to finding part time work to pay for flying lessons, or at least the ground school portion. Get your private pilot license, and devote yourself to building your flight time. As a paramedic, you could find a job with a helicopter or airplane medivac flight service. Give it time; you will build time and experience, and the doors will begin to present themselves. It will be up to you to figure out which ones to knock on or beat down.

So you'll know where I'm coming from, I'm 52 yrs. old, and didn't have the slightest damn notion of what I wanted to do when I was 18, didn't start figuring it out until I was about 25, when I started college to become a Registered Nurse. Although I've always loved airplanes, space, etc., I never considered aviation as a career until I was 32, when I joined the US Air Force, and served 8 years as a Flight Nurse (C-130's and C-141B's) including service during the 1st Gulf War (Desert Storm). I took the FAA ground school in 1992, but the eoconomics of the time, I figured I couldn't afford to stay current enough to be a safe pilot, so I didn't pursue it (was married with 1st kid on the way). I always regretted not doing all that when I was about your age. I just started R/C flying about 4 years ago.

Bottom line: you think you know what you want to do. Focus all your attention and time on those things, and don't let ANYTHING divert you from that course. Good luck, Ken