One need not necessarily be good in just one form of drawing; an artist can be good in multiple forms. This can be identified only by trying. One should not restrict themselves to the drawing form they are most familiar with and are experienced in. you may have learnt a particular form but that must not stop you from trying your hand with other materials.
If you are a pencil sketch artist, you can widen your horizon by trying color pencils. Though black and white is classic and beautiful in its own way, colors have a way of bringing more life to the art form. Some paintings or drawings will look better with colors. This is because we are surrounded by colors and incorporating them into your drawing will add more life to the sketch.
When different shades are used, the technique needs to be mastered. The strokes, the pressure exerted, the mixing of colors, etc, should all be taken care of. One can do this out of practice. Try using some color pencils to your otherwise black pencil sketches and learn to use the different shades. One can even join the number of classes available both online and offline, and get some professional help.