27 is a pivotal age career-wise.
Trucking is a lonely profession, and I don't know a trucker who didn't develop drinking and drug abuse problems before long. Luckily, you already have a head start.
My recommendation is to take any job you can get and explore. It sounds to me like you are looking for something to find. Go find it, and stop trying to decide what it will be when you do.
I spent years working as an attendant at an underground parking garage. I read a lot, and then got the fuck out of there with some knowledge and a lot of optimistic dreams. Then I went on a walkabout, working here and there, moving cities, and bang, one day someone found me interesting enough to pay a lot of money to and to send travelling around the world. All I wanted was to see the world (without shooting people), and figured that if I did, I would find money along the way. I have a degree, but it is worthless on its own (History and Classics) - it does come in handy however, when applying for residence visas in other countries - any degree is fine, and has as much power in the situation as a passport.
Study what you love, follow passions, and don't let school get in the way of a good education. Of course, I am handsome, charming, and have a big cock, so I can get away with this kind of bubble.