Am I just a fuddy-duddy, or do all moms feel like this?

So, it's December third, I have three projects to finish-up, four exams to study for, and a research paper to write...all within the next two weeks.  I don't care about the Christmas-present-tradition, and don't really want to put-up our tree this year.

I'm a wife, mother of a five-month-old son, full-time student, and have a house, two cats and two dogs to care for.  I'm exhausted, experiencing severe morning joint-pain (I'm only 25) and have a headache most of the time.  I don't want to be a scrooge, but I have no time or energy for seasonal excitement.

The real question, I guess, is: How do I pretend to be in seasonal bliss when I don't even have time or energy to shave my legs or cut my nails?

I'm new to this whole mother, and home-owner thing; so I guess I am looking for some advice.