Is this too much chocolate for one girl?

Emily really loves chocolate, but lately she has been indecisive on what kinds of chocolate to eat. She currently has a collection of various chocolate squares of 1 square inch, 2 square inches, and 3 square inches.

Type $\quad$ # of 1 square" $\quad$ # of 2 square" $\quad$ # of 3 square"

Milk $\quad$ $\quad$ $\quad$ 5 $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ 3 $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ 7

White $\quad$ $\quad$ 4 $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ 2 $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ 1

Dark $\quad$ $\quad$ 2 $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ 3 $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ 2

If Emily is only allowed to eat 18 or less square inches of chocolate today, then how many combinations can she choose from to eat her chocolate?