It's really good work you can be proud of your progress. The gestures are very dynamic for a 3 month old beginner. You can take the next step and now get out of your "comfort zone" to try shading.
A good tip: You can very lightly draw the outlines that catch the light and accentuate the shadows with thicker outlines or with a bolder pencil. Having several pencils really helps (HB, 2B and 5B for example) to bring out the shadows :)