You're alright dude. You're relatively young (Christ, I'm only 23 and feel like your elder writing you this!

) Most of my buddies who packed up and left town are "professional college students" and have 6-7 year major's that is seriously certifiably insane for any human being to endure unless you're going to send a rocket ship to the moon or solve the cure for cancer. I've already been pulled in so many directions in just a 1 year's notice and had to do what I had to do to make money. I started working for my brothers Silkscreen company at 17 and saw the boom of his business (even did shirts for Neal! Neal Schon's Afro Society t-shirts) but differences and curiosity led me to a different direction. To give myself some time to reflect and what I wanted, I held a steady but VICIOUS paper-route for 3 years before deciding to re-enlist in school and take a chance. Going out on a limb is what you need to do. The mind is a powerful thing. I enlisted into the Information Technology (I.T) field and it was pretty much like starting all over and gave myself an identity. I completed my coarse, went through externs, have to go through an internship and have the pressure of my school breathing down my neck on landing interview after interview, let alone taking exams to become certified (that I'm currently working on at this very moment) and had a GPA of 3.5, all which seemed impossible just a few years earlier.
I, too, felt like yourself at one point. In today's society, especially our generation, the pressure is monumental for us to perform and start a family of our own by a certain age (like John said, 25ish.) I'm 23 and made the decision to go after something rather than sitting around and waiting for something to come to me. Got to go out on a limb, even if it doesn't peak your interest. Take it from me, I was born and bred to be a Steel Mill worker, my father, who is a top boss at one of the top Steel Mill's in the Pittsburgh area, could land me a job in the industry starting out at $30.00 an hour but I chose to go on and find myself.
You're young, only 21 years old. Give it time for the mature in your mindset to kick in because within a couple years notice, everything can turn around and change for the better. And if it doesn't work out, you can always hang your hat on the fact that you tried and tried again to find yourself from within. You might not have it now, but the confidence will come. Just give yourself a chance and be ready, when you're ready!