The period of y = sin(kx) is . In your case k = 2 so the period is . The graph of y = sin x is therefore dilated by a factor of 1/2 in the horizontal direction.

If you're using a table of values to assist your sketching efforts, you should use values of x such as -pi/2, -pi/4, 0, pi/4, pi/2 rather than the values you have chosen ....