Hey, dude, don't worry. There's plenty of undergrads here. I just turned 18 years old myself on July 3 (yes, I have the same birthday as Tom Cruise ).
Besides, from what I hear college is actually a lot of fun...if you get involved that is. I'm going to enjoy my college years, and doubt if I'd enjoy my medical schools as much, as when I'm a medical student, I'll probably be too bogged down by science classes.
I haven't even started my undergrad yet (well, not technically). My first classes as a freshman begin in late August.
Let's talk about how fun college is and how we're preparing as pre-meds during the coming years, shall we?