Improvements, Big and Small

So, for the last few weeks, I've been almost regularly going to the gym.  Mainly jogging and fast walking on the treadmill, but also using the machines to strengthen my arms, legs, and core.  Of course, when I first began, I realized just how out of shape I was - barely able to keep up with the 'mill set to 3.0 speed, let alone 4.0 or 5.  Barely able to do on set one the abdominal, not even really able to do a sit up or push up.  Wanting to cry after two seconds of a plank.

Has it really just began?

I'm tired.  I'm not talking in the physical sense, either - I mean in a resounding, mental and emotional sense.