Yep, when I was a Senior in HS, I had big dreams too. Many that enter college thinking they know what they want to do, change their minds mid program. You have time to figure this out for yourself and there will be some general classes to get out of the way first (prerequisites) anyway.
There are 3 types of science people (in general) as I see it.
1: There are the academics. Those are the people who go through the education in their chosen field and never leave the university setting. They stay, if tenured, applying for research grants and doing all their work within the walls of the university. Naturally, they are also the professors but I've never seen any of these people actually teach a class. They have their research assistants do it (when you go for your masters degree, that's what you'll be doing, somebody else's work).
2: There are the corporates. These are the folks who get their educations and spend the rest of their lives in a corporation run lab somewhere. The amount and type of work you do here will depend on what the company is going to support.
3: Finally there are the freelancers. That is somewhat an ambiguous term because it implies someone who just goes off gallivanting around the world chasing after something. Partially true. These people choose a specific area of their given field and focus only on that. They may work for a corporation or even the university at some level but they decide where and how their research takes them.
Photography can be combined with any pursuit. If you're thinking about having somebody Pay you to do it, then do it as a sideline only. That's my suggestion anyway. There are billions of people in this world and I'd wager at least half of them have cameras and internet access. I call them freelancers. That is, they take their photos and hope someone will buy them for publication of some sort. Paying jobs are more likely to involve war zones or disaster areas. That is, unless you are standing outside of a club in Hollywierd hoping to get the next crotch shot of Brittany Spears.
As for striking out on your own and learning to do for yourself, we all go through it, most of us survive it. There are a few who never learn but those are the 'special' cases.
Bottom line, you have time. Your college career may not survive your first intentions. That's what the first couple years are for.