To the OP, I was in your boat not too long ago.. At least it seems that way. The next 6-7 years are going to fly by and they are important. That said, go have fun. Keep a relatively open mind and experience all that you can, within reason. Keep your eyes on the big picture and find a mentor in the career fields that interest you. They can help you decide what you want to do if you don't already know.

There will be tough times, there will be times you may think you can't do something or something seems impossible. Life changes fast and nothing is permanent as long as you stay persistent and keep a positive attitude. Best of luck to you man.