In a composition, is time of day considered to be pathetic fallacy?
On it's own, no. Add some human attributes and then maybe. See below for more:
Pathetic Fallacy is when inanimate parts of nature are given human attributes. For example, this is pathetic fallacy:
The sky angrily roared it's fury.
Having a scene set in a time of day is not, in and of itself, pathetic fallacy. However, if we look at an excerpt from Macbeth (the full example is in the link below), we can see that this passage is pathetic fallacy:
The night has been unruly.
So for a time of day to have pathetic fallacy, we need to impart human attributes or qualities. Something like this, for example (looks like I threw in two pathetic fallacies - the first is for time of day and the other... just because...):
Math class should never be a last period class. Ever. I glance at the clock at what I perceive to be regular intervals and yet it seems to slow down. Time itself drags its feet, like a child before bedtime unwilling to walk the last few feet to a bedroom and, ultimately, sleep. Even the very air gets in on the act; the heavy-handed atmosphere of the room unwilling to make the effort to reach my lungs and grant me life for these hours-long last few minutes of Pythagorean hemispheres having statistical ratios of sinusoidal concordance... or whatever it is Mr. Wundermeth is droning on about.