Too old for college?

Is 21 too old to be a freshman in college? I didn't go right out of high school. I visited a friend on her campus and it made me want to pursue an education. I'm going to a college visit on Thursday and I feel a little silly. My friend said that some guy on their basketball team just started college at the age of 25 and she called him old. I already have social anxiety so I'm afraid I'll feel weird and out of place!