I feel like I missed out by not going to a prestigious university. How do I overcome this?

As I look back on my education, I realize I got a wonderful jump-start at Columbia University.  I also realize that in the 4 years I spent there, I learned a lot.  It probably adds up to about 0.5% of what I know now.

The university is only the beginning of your education.  A great university gives you a great beginning.  But a head-start is less important than endurance. Slow and steady wins the race. If you keep learning, every day, every week, soon whatever you "missed" at the university will fade into nothingness.

When I graduated from Columbia, I was annoyed that the ceremony was not called a graduation, but was called a "commencement".  Hey, I wanted recognition for the four years of work I had struggled through!  

In retrospect, that was exactly the right name.

As you grow older, you'll see many of your friends and colleagues become couch potatoes, with their bodily health and strength gradually going downhill.  Don't let it happen to you.  But far worse, their brains will also go downhill.  Not forced to learn, they will stop learning.  Don't let it happen to you!

Every year of your life, learn more than you did last year.  It gets easier to do this as you get older, because the main thing you learned in college was how to learn. And you can keep getting better at it.

The key to learning is recognizing how much fun it is.  When you enjoy something, you learn without effort.  In college, I had no interest in history, little in world affairs; now those subjects fascinate me.  I find almost all of life fascinating.

Forgive me for ending with a cliche: 
This is the first day of the rest of your life.