Trying to Feel Infinite

I’m taking a lifeguard certification class next semester (starting Tuesday)…

…and I’m really nervous about wearing a bathing suit in front of people, especially since my school is filled with “guidettes” (I go to school practically on the beach in NJ and half the school population thinks they’re on “Jersey Shore”…).
But everyone is like, 120 pounds of tanned, short, pretty, toned skinniness.
And I’m 140 pounds of pale, tall, plain-looking, flabby awkwardness.

I know I shouldn’t care what people think about me, but I have that terrible feeling that I’m going to be the least-fit girl in the class and I’m going to look like a freaking whale when I jump in the pool.
I’ll probably wear a lap suit instead of a bikini since it’s more practical for a lifeguard certification course anyways, but I know I’ll be nervous having to get into the pool in front of people.