You can still go to college, even a community college would get you a basic degree in what you're interested in.
If you are INTERESTED in modeling then find somewhere that can help you get started. Search for modeling training for men in your area (google will find results easily, I had been in female modeling for a while, but decided make-up is SO not me).
If you really want to pursue a career having to do with animals then try looking at a zoo, you could get a simple job there even as simple as cleaning up after the animals, it may not be very glorious, but if you love animals that much then it could end up being quite enjoyable for you. If that doesn't strike your fancy then you could try opening a shelter, go to a university for a couple years, get a basic business education and license, and open up a rescue for dogs/cats/small animals, or whatever you like.You could even go into working AT a shelter. It may not pay the best, but it can be a very rewarding job.
As for film or acting, try looking for auditions for commercials/ TV shows/ or even movie extras (or mains, depending on your skill confidence pertaining to acting) and go try out! You could hit a good streak and end up being on the big screens in the next few years. You could even get a degree in teaching and TEACH acting. Or even just start a little shindig where you charge people for acting tips or something. Anything to get your started.
If you want to direct movies then start a low budget directing deal and start looking for people who want to make movies. You could film movies, produce DVD's, and sell them in movie stores (although they normally don't catch the buyer's eye if it's not a big-shot movie).
Try at least going for your bachelors degree for general studies so you have some base to build up from. If you don't do it now, the regret you feel currently will only increase ten fold by the time you're in your 30's.