it seems like its normal to feel either energized or relaxed but yawning and feeling too tired to move might not be (which is how i feel most of the time).
After a good workout, my muscles can feel tired and looser or relaxed but my brain is energized and I'm more likely to jump up and do something, even something that seemed like too much prior to exercising. I'm not exercising to exhaustion though.
When I was on the flip side and more exhausted after exercising, I could be wiped out by a short workout, and not feel well afterwards. There was no feeling of being energized. I would feel worse than before I started. I could however strength train and feel ok afterwards.
I haven't tried creatine, but I will look that up.