(I respect all the previous opinions. But, obviously, with my saying that, I am about to refute some of them. But, also, I agree with many of the, so I am just rehashing points, but in a more robust and frankly unnecessary many. Many grievances below.)
Foremost, just go. I don't think it involves much further thought than that. Put on pants, put on a shirt (long-sleeve if you are in the Northern hemisphere), put on shoes, and show up the concert. Being in law school, I can still reap the benefits of student prices. Amazing stuff. I plan to abuse my student ID for ten more years, until my face grows wrinkles and sheds youth.
Now, given that, I should at least comment on a few personal grievances re classical concerts and what not:
1. Classical music is not a young person's affair. That is just the reality. I am only 24, so I am of your generation. I have written previously on this forum that, sans a university, music school graduate outing, you are not going to be attending classical music concerts with people of your generation. It just isn't going to happen. Maybe you'll see people your age. But, like, what? 10 percent? 15 percent of the concert hall?
2. So, why does #1 matter? Well, given that reality, classical concerts are -- recall, my own grievance here -- overwhelmingly haughty, uptight, strict, and rather absurd events. People dress up. People smell of products and fragrance. People drink wine and other fancy cocktails. People expect others to do the same.
The whole act of attending the classical concert -- opera, symphony, chamber, whatever -- is an outdated and frankly snobby affair. It is an antiquated culture. Truly, I am disappointed every time I venture out to the concert hall, because things still have not changed.
Anyways, what does this have to do with music? Nothing! Nothing!
And nothing comes from nothing! Show up with your own wear, your own attitude, your own expectations, and your own gestalt. As much as I look forward to every concert I attend, I grow more and more repulsed with this cultural ambiance.
Granted, where I live, showing up in with a bike helmet, jeans, baseball-tee, maybe a bandana -- no one really frowns on you. For this, I am grateful, and I acknowledge it. But I could not imagine doing this in Texas (sorry...) or some renown, fancy recital hall in New York or a European city. I would be judged, heavily.
Though, in the end, when I attend a concert, I am only waiting for that eighty-eighth measure, the one with the brass and climax, the one where the rest of the audience jump in their seats because they were not expecting that, and have never heard the piece, and are hear because a friend brought them, or they have money to spend, or they wanted something to do on this Saturday evening.
So, ha! That is the truth, right? The Music is why you attend, not the people or community. You are there for the music, not for the appearance. You come to listen, not to look good in a suit, or even a polo. You are there because notes and melodies make you feel something.
In sum, especially if you skip to the bottom of this post, attend the concert. Dress how you want. Get whatever seat you want. The single reason you attend is for the music. That is all.