Looks good, Kathy
The slanting corners bother me, I assume that you drew them vertically ?
This is the typical deformation that you get if you tilt
the camera/smartphone with respect to the plane of the drawing.
Another point to consider is the choice of the eye level. The EL is
the level where the imagined observer in the picture has his eyes. That is in normal circumstances not at the level of the gutters
As for the columns, cylinders are in next class. And you're ready for next class, please move on