[Powerofmene]

Wow, are you a physician? There are a myriad of reasons this could be happening starting with something as innocent as adjusting. Sitting all day and staring at a computer screen can be exhausting.

Health reasons could be causing exhaustion from low vitamin levels, poor diet, thyroid issues etc. Depression is possible but to throw out something like without a thorough medical work up and off of just a few statements is irresponsible. The OP said nothing about no wanting to get out of bed, not wanting to communicate or be around people, or any of the classic signs of depression nor did he/she mention anything such as feeling blue etc. quite the opposite, enjoys his work, etc. If all it takes is enjoying your job and being exhausted at the end of the day to be diagnosed with depression there would be far more than 10% of US adults with depression.

To the OP, If working out does not raise your energy levels I would suggest having a medical work up to rule out imbalances that are easily remedied. Working out does take time and requires consistency in order to raise energy levels but if it does not then you may need to talk to a physician.