Now that all the newness of the school year is settling down and routines are being formed, it is easy to start being more critical. Sometimes something you thought would be exciting, like a class, turns out to be not what you wanted and the add/drop period is long gone. But instead of sitting and stewing, reframe your expectations and find something that you can glean from the class. It may not be what you intended but every experience is a learning experience.
I believe that as a culture/society/race?!?! we tend to focus on the negative. Maybe it is a bounding behavior, commiserating on the bad experience, 'that was a waste of time', 'can you believe all the boring homework', 'that was the worst lecture', blah, blah blah.
However, I find focusing on the negative is a waste of time and energy, so instead of brooding find something that you can take away from the situation, something that will capture your curiosity.
Believe it or not, being in school is a blessing make the most of it.