The opening A section was a symmetric double parallel period, with 2- 4 measure phrases in each phrase. The second phrase of the first period starts out a fifth higher (c# the first phrase, g# the Both hands start out in treble clef, but the left hand is constantly switching clefs throughout the piece. The theme (the 1st 2 measures of the piece) are restated in measures 16 and 17, right before the pickup B section begins. The A section closes in the same key as it began, so it is a closed section.
The B section is much smoother in sound than the A; the density of the notes also changes, to more of a chordal sound. The key changes to g major, and is very short compared to the A section. However, it is closed because it modulates to a new key (back to g minor),This has only one period, which i thought was asymmetric (the first phrase being 4 measures, and the second being two. Then the pickup in measure 24 takes us back to the A section again. The restatement of the A section is almost identical. I noticed that the tempo is almost always pushed back at the very end of each period, which is really pretty to listen to. Since this is in ABA form, it is in simple ternary form...The end.