I agree with the earlier comments. 23 is plenty young. You have so much time to figure out what you want to do with your life. My advice is not to worry about 28 being the end of the good times or even necessarily your prime. That's kind of a sad way to live, thinking that life's best times will be over before you even reach your halfway point! Instead, try to visualize life getting better as it goes on.

At any rate, good luck figuring out what you'll do!