When I was in college, I decided that I my bike (a decent full-suspension Giant MTB) needed to be upgraded. There were definitely issues - the chainrings and cassette were worn from a lack of chain maintenance - but I went about the upgrades in the wrong way. Rather than taking a slow, reasoned approach, with the advice of people here and at my LBS, I went out and purchased an entire set of Park tools, a new crank and chainring set, and a new cassette - all without bothering to check whether they'd be the right components for my bike. After dismantling the bike and fitting the new parts, nothing worked properly, and I was out hundreds of dollars. I ended up taking my younger brother's bike, which he no longer used, and building it up as a commuter. My Giant bike has been collecting dust for almost a decade now.
In short, you've made a good decision to wait - as you gain more experience and knowledge, you'll have a better idea of what you actually want. I also recommend reading as much as you can about your bike's mechanical components - these forums and Sheldon Brown's web site are great places to start.