If I increase the number of motors in a parallel circuit, will my current increase?
If you put two identical resistors in parallel, the resulting resistance is 1/2 of each resistor. Therefore, twice as much current will be drawn from the power source. 

So, yes, if you put four motors in parallel, they will try to draw quadruple the current as one. (Actually, not quite 4x as the internal resistance of the battery will drop the voltage to some degree.)