What now? That's certainly not advice I'd be giving.
@
FullMoon
Yes, you certainly don't want to overestimate yourself in your freshman year, stick with 15 for at least two. Taking 17-18 credits in your sophomore/junior years is a perfectly fine option, given that you feel that you're capable of it. I managed part-time work, family care, social life, and grades fine in two separate 18 credit semesters.
Sleep is for ****ies.
Of course, it's also dependent on what you plan on studying. CS major/Econ minor here talking, I wouldn't know much about other academic concentrations. Best of luck. You claim to be timid now, chances are you'll be having a blast within a few months. The easiest way to make friends is to sit with people in lecture who're in your same recitation, you'll chat them up in no time.