I'm trying to include my vector class

#include "math/Vec2.h"

and Vec2.h is obviously in the math directory.

I have no idea how this is happening, but when I try to compile I get "math/Vec2.h: no such file or directory"

I have another file in the math directory called "Mat3x3.h" which I can include just fine:

#include "math/Mat3x3.h" //no problem

What could I possibly be doing wrong? Obviously I've double checked the filename for any typos.